Rapidly deployable surgical heart valves

ABSTRACT

A quick-connect heart valve prosthesis that can be quickly and easily implanted during a surgical procedure is provided. The heart valve includes a substantially non-expandable, non-compressible prosthetic valve and a plastically-expandable frame, thereby enabling attachment to the annulus without sutures. A small number of guide sutures may be provided for aortic valve orientation. The prosthetic valve may be a commercially available valve with a sewing ring with the frame attached thereto. The frame may expand from a conical deployment shape to a conical expanded shape, and may include web-like struts connected between axially-extending posts. A system and method for deployment includes an integrated handle shaft and balloon catheter. A valve holder is stored with the heart valve and the handle shaft easily attaches thereto to improve valve preparation steps.

RELATED APPLICATIONS

The present application is a divisional of U.S. Ser. No. 13/167,639,filed Jun. 23, 2011, which in turn claims priority under 35 U.S.C.§119(e) to U.S. provisional application No. 61/381,931 filed Sep. 10,2010.

FIELD OF THE INVENTION

The present invention generally relates to prosthetic valves forimplantation in body channels. More particularly, the present inventionrelates to unitary surgical prosthetic heart valves configured to besurgically implanted in less time than current valves, and associatedvalve delivery systems.

BACKGROUND OF THE INVENTION

In vertebrate animals, the heart is a hollow muscular organ having fourpumping chambers as seen in FIG. 1—the left and right atria and the leftand right ventricles, each provided with its own one-way valve. Thenatural heart valves are identified as the aortic, mitral (or bicuspid),tricuspid and pulmonary, and are each mounted in an annulus comprisingdense fibrous rings attached either directly or indirectly to the atrialand ventricular muscle fibers. Each annulus defines a flow orifice.

The atria are the blood-receiving chambers, which pump blood into theventricles. The ventricles are the blood-discharging chambers. A wallcomposed of fibrous and muscular parts, called the interatrial septumseparates the right and left atria (see FIGS. 2 to 4). The fibrousinteratrial septum is a materially stronger tissue structure compared tothe more friable muscle tissue of the heart. An anatomic landmark on theinteratrial septum is an oval, thumbprint sized depression called theoval fossa, or fossa ovalis (shown in FIG. 4).

The synchronous pumping actions of the left and right sides of the heartconstitute the cardiac cycle. The cycle begins with a period ofventricular relaxation, called ventricular diastole. The cycle ends witha period of ventricular contraction, called ventricular systole. Thefour valves (see FIGS. 2 and 3) ensure that blood does not flow in thewrong direction during the cardiac cycle; that is, to ensure that theblood does not back flow from the ventricles into the correspondingatria, or back flow from the arteries into the corresponding ventricles.The mitral valve is between the left atrium and the left ventricle, thetricuspid valve between the right atrium and the right ventricle, thepulmonary valve is at the opening of the pulmonary artery, and theaortic valve is at the opening of the aorta.

FIGS. 2 and 3 show the anterior (A) portion of the mitral valve annulusabutting the non-coronary leaflet of the aortic valve. The mitral valveannulus is in the vicinity of the circumflex branch of the left coronaryartery, and the posterior (P) side is near the coronary sinus and itstributaries.

Various surgical techniques may be used to repair a diseased or damagedvalve. In a valve replacement operation, the damaged leaflets areexcised and the annulus sculpted to receive a replacement valve. Due toaortic stenosis and other heart valve diseases, thousands of patientsundergo surgery each year wherein the defective native heart valve isreplaced by a prosthetic valve, either bioprosthetic or mechanical.Another less drastic method for treating defective valves is throughrepair or reconstruction, which is typically used on minimally calcifiedvalves. The problem with surgical therapy is the significant insult itimposes on these chronically ill patients with high morbidity andmortality rates associated with surgical repair.

When the valve is replaced, surgical implantation of the prostheticvalve typically requires an open-chest surgery during which the heart isstopped and patient placed on cardiopulmonary bypass (a so-called“heart-lung machine”). In one common surgical procedure, the diseasednative valve leaflets are excised and a prosthetic valve is sutured tothe surrounding tissue at the valve annulus. Because of the traumaassociated with the procedure and the attendant duration ofextracorporeal blood circulation, some patients do not survive thesurgical procedure or die shortly thereafter. It is well known that therisk to the patient increases with the amount of time required onextracorporeal circulation. Due to these risks, a substantial number ofpatients with defective valves are deemed inoperable because theircondition is too frail to withstand the procedure. By some estimates,about 30 to 50% of the subjects suffering from aortic stenosis who areolder than 80 years cannot be operated on for aortic valve replacement.

Because of the drawbacks associated with conventional open-heartsurgery, percutaneous and minimally-invasive surgical approaches aregarnering intense attention. In one technique, a prosthetic valve isconfigured to be implanted in a much less invasive procedure by way ofcatheterization. For instance, U.S. Pat. No. 5,411,552 to Andersen etal. describes a collapsible valve percutaneously introduced in acompressed state through a catheter and expanded in the desired positionby balloon inflation. Although these remote implantation techniques haveshown great promise for treating certain patients, replacing a valve viasurgical intervention is still the preferred treatment procedure. Onehurdle to the acceptance of remote implantation is resistance fromdoctors who are understandably anxious about converting from aneffective, if imperfect, regimen to a novel approach that promises greatoutcomes but is relatively foreign. In conjunction with theunderstandable caution exercised by surgeons in switching to newtechniques of heart valve replacement, regulatory bodies around theworld are moving slowly as well. Numerous successful clinical trials andfollow-up studies are in process, but much more experience with thesenew technologies will be required before they are completely accepted.

Accordingly, there is a need for an improved device and associatedmethod of use wherein a prosthetic valve can be surgically implanted ina body channel in a more efficient procedure that reduces the timerequired on extracorporeal circulation. It is desirable that such adevice and method be capable of helping patients with defective valvesthat are deemed inoperable because their condition is too frail towithstand a lengthy conventional surgical procedure.

Furthermore, surgeons relate that one of the most difficult tasks whenattempting minimally invasive heart valve implantation or implantationthrough a small incision is tying the suture knots that hold the valvein position. A typical aortic valve implant utilizes 12-24 sutures(commonly 15) distributed evenly around and manually tied on one side ofthe sewing ring. The knots directly behind the commissure posts of aprosthetic aortic valve are particularly challenging because of spaceconstraints. Eliminating the need to tie suture knots or even reducingthe number of knots to those that are more accessible would greatlyfacilitate the use of smaller incisions that reduces infection risk,reduces the need for blood transfusions and allows more rapid recoverycompared to patients whose valves are implanted through the fullsternotomy commonly used for heart valve implantation.

The present invention addresses these needs and others.

SUMMARY OF THE INVENTION

Various embodiments of the present application provide prosthetic valvesand methods of use for replacing a defective native valve in a humanheart. Certain embodiments are particularly well adapted for use in asurgical procedure for quickly and easily replacing a heart valve whileminimizing time using extracorporeal circulation (i.e., bypass pump).

In one embodiment, a method for treating a native aortic valve in ahuman heart to replace the function of the aortic valve, comprises: 1)accessing a native valve through an opening in a chest; 2) placingguiding sutures in the annulus 3) advancing a heart valve within a lumenof the annulus; and 4) plastically expanding a metallic anchoring skirton the heart valve to mechanically couple to the annulus in a quick andefficient manner.

The native valve leaflets may be removed before delivering theprosthetic valve. Alternatively, the native leaflets may be left inplace to reduce surgery time and to provide a stable base for fixing theanchoring skirt within the native valve. In one advantage of thismethod, the native leaflets recoil inward to enhance the fixation of themetallic anchoring skirt in the body channel. When the native leafletsare left in place, a balloon or other expansion member may be used topush the valve leaflets out of the way and thereby dilate the nativevalve before implantation of the anchoring skirt. The native annulus maybe dilated between 1.0-5 mm from their initial orifice size toaccommodate a larger sized prosthetic valve.

In accordance with a preferred aspect, a heart valve includes aprosthetic valve defining therein a non-expandable, non-collapsibleorifice, and an expandable anchoring skirt extending from an inflow endthereof. The anchoring skirt has a contracted state for delivery to animplant position and an expanded state configured for outward connectionto the surrounding annulus. Desirably, the anchoring skirt isplastically expandable.

In another aspect, a prosthetic heart valve for implant at a heart valveannulus, comprises:

-   -   a. a non-expandable, non-collapsible annular support structure        defining a flow orifice and having an inflow end;    -   b. valve leaflets attached to the support structure and mounted        to alternately open and close across the flow orifice;    -   c. a plastically-expandable frame having a first end extending        around the flow orifice and connected to the valve at the inflow        end of the support structure, the frame having a second end        projecting in the inflow direction away from the support        structure and being capable of assuming a contracted state for        delivery to an implant position and a wider expanded state for        outward contact with an annulus; and    -   d. a fabric covering around the plastically-expandable frame        including an enlarged sealing flange surrounding the second end.

Preferably, the support structure includes a plurality of commissureposts projecting in an outflow direction, and the valve leaflets areflexible and attached to the support structure and commissure posts andmounted to alternately open and close across the flow orifice. Also, asealing ring desirably circumscribes an inflow end of the supportstructure. The enlarged sealing flange surrounding the second end of theplastically-expandable frame is spaced from the suture permeable ring tohelp conform the frame to the aortic annulus.

In one embodiment, the heart valve comprises a commercially availableprosthetic valve having a sewing ring, and the anchoring skirt attachesto the sewing ring. The contracted state of the anchoring skirt may beconical, tapering inward from the first end toward the second end, whilein the expanded state the frame is conical but tapering outward from thefirst end toward the second end. The anchoring skirt preferablycomprises a plurality of radially expandable struts at least some ofwhich are arranged in rows, wherein the distalmost row has the greatestcapacity for expansion from the contracted state to the expanded state.The sewing ring may comprise a solid yet compressible material that isrelatively stiff so as to provide a seal against the annulus and has aconcave inflow shape that conforms to the annulus.

A method of delivery and implant of a prosthetic heart valve system isalso disclosed herein, comprising the steps of:

-   -   a. providing a heart valve including a prosthetic valve having        an expandable frame, the frame having a contracted state for        delivery to an implant position and an expanded state configured        for outward connection to the annulus, the heart valve being        mounted on a holder having a proximal hub and lumen        therethrough, the proximal hub connected to the distal end of a        handle shaft having a lumen therethrough,    -   b. advancing the heart valve with the frame in its contracted        state to an implant position adjacent the annulus;    -   c. passing a first balloon catheter through the lumens of the        handle shaft and the holder and within the heart valve, and        inflating a balloon on the first balloon catheter;    -   d. deflating the balloon and retracting the first balloon        catheter from within the heart valve, and removing the first        balloon catheter from the handle shaft;    -   e. inserting a second balloon catheter into the handle shaft and        passing the second balloon catheter through the lumens of the        handle shaft and the holder to within the heart valve, and        inflating a balloon on the second balloon catheter to expand the        frame.

The method may involve increasing the orifice size of the heart valveannulus by 1.0-5.0 mm by plastically expanding the frame. In oneembodiment, the prosthetic valve of the valve component is selected tohave an orifice size that matches the increased orifice size of theheart valve annulus.

The heart valve in the aforementioned method may include anon-expandable, non-collapsible orifice, with the expandable framecomprising an anchoring skirt extending from an inflow end thereof. Theanchoring skirt may have a plurality of radially expandable struts,wherein a row farthest from the prosthetic valve has alternating peaksand valleys. The distal end of the anchoring skirt desirably has thegreatest capacity for expansion from the contracted state to theexpanded state so that the peaks in the row farthest from the prostheticvalve project outward into the surrounding left ventricular outflowtract.

One embodiment of the method further includes mounting the heart valveon a holder having a proximal hub and lumen therethrough. The holdermounts on the distal end of a handle shaft having a lumen therethrough,and the method includes passing a balloon catheter through the lumen ofthe handle shaft and the holder and within the heart valve, andinflating a balloon on the balloon catheter to expand the anchoringskirt. The heart valve mounted on the holder may be packaged separatelyfrom the handle shaft and the balloon catheter. Desirably, thecontracted state of the expandable frame/anchoring skirt is conical, andthe balloon on the balloon catheter has a larger distal expanded endthan its proximal expanded end so as to apply expansion deflection tothe anchoring skirt and not to the prosthetic valve. In a preferredembodiment, the balloon distal and proximal diameters are essentiallythe same, the balloon being generally symmetric across an axial midline,and the balloon midline is positioned near the distal end of the frameprior to inflation. The delivery system including the valve holder isdesigned to position the balloon within the heart valve so that itinflates within the anchoring skirt, and not within the actual valvecomponents.

Preferably, a valve delivery system includes an integrated ballooncatheter and tubular handle shaft through which the catheter extends. Adistal end of the handle shaft includes an adapter which mates with aholder of the heart valve, and a locking sleeve for rapidly connectingthe delivery system to the heart valve holder. A balloon of the ballooncatheter resides within the adapter and may be advanced distally intoposition for expanding the anchoring skirt. A tubular balloon introducersleeve attached when removing the heart valve from a storage jarfacilitates passage of the balloon through the heart valve.

Another aspect described herein is a system for delivering a heart valveincluding a prosthetic valve having a non-expandable, non-collapsibleorifice, and an expandable frame extending from an inflow end thereof,the frame having a contracted state for delivery to an implant positionand an expanded state. The delivery system includes a valve holderconnected to a proximal end of the heart valve, a balloon catheterhaving a balloon, and a malleable handle shaft configured to attach to aproximal end of the valve holder and having a lumen for passage of thecatheter, the balloon extending distally through the handle shaft, pastthe holder and through the heart valve.

The balloon catheter desirably has an inflation tube that extendsthrough the lumen of the handle shaft and the OD of the inflation tubeis more than 90% the ID of the handle shaft lumen. The prosthetic valvemay be a commercially available valve having a sewing ring, and whereinthe frame attaches to the sewing ring. The contracted state of the frameis preferably conical, tapering down in a distal direction. Further, theballoon may include a visible midline that is positioned near the distalend of the frame prior to inflation. In a preferred embodiment, theheart valve mounted on the holder is packaged separately from the handleshaft and the balloon catheter. The malleable handle shaft may be madeof aluminum.

In one embodiment, the expandable frame is an expandable anchoring skirtformed of plastically-deformable struts surrounded by a fabric cover,and an enlarged sealing flange surrounds the second end of theplastically-expandable frame spaced from a sewing permeable ring on thevalve to help conform the frame to the aortic annulus.

A further understanding of the nature and advantages of the presentinvention are set forth in the following description and claims,particularly when considered in conjunction with the accompanyingdrawings in which like parts bear like reference numerals.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained and other advantages and featureswill appear with reference to the accompanying schematic drawingswherein:

FIG. 1 is an anatomic anterior view of a human heart, with portionsbroken away and in section to view the interior heart chambers andadjacent structures;

FIG. 2 is an anatomic superior view of a section of the human heartshowing the tricuspid valve in the right atrium, the mitral valve in theleft atrium, and the aortic valve in between, with the tricuspid andmitral valves open and the aortic and pulmonary valves closed duringventricular diastole (ventricular filling) of the cardiac cycle;

FIG. 3 is an anatomic superior view of a section of the human heartshown in FIG. 2, with the tricuspid and mitral valves closed and theaortic and pulmonary valves opened during ventricular systole(ventricular emptying) of the cardiac cycle;

FIG. 4 is an anatomic anterior perspective view of the left and rightatria, with portions broken away and in section to show the interior ofthe heart chambers and associated structures, such as the fossa ovalis,coronary sinus, and the great cardiac vein;

FIGS. 5A and 5B are perspective views of an exemplary prosthetic heartvalve of the present application assembled on a valve holder;

FIGS. 6A and 6B are perspective view of the valve holder of FIGS. 5A and5B separated from the heart valve;

FIGS. 7A-7D are orthogonal views of the exemplary prosthetic heart valveand valve holder;

FIGS. 8A-8C are elevational, plan, and sectional views of the exemplaryvalve holder;

FIG. 9 is an exploded view of an inner structural band subassembly ofthe exemplary prosthetic heart valve;

FIG. 10 is a perspective view of a further valve subassembly of anundulating cloth-covered wireform, and FIG. 10A is a detailed sectionalview of a cusp portion thereof;

FIG. 11 is a perspective view of the band subassembly and asuture-permeable sewing ring joined together, and FIG. 11A is a radialsectional view through a cusp portion thereof;

FIGS. 12A and 12B are inflow and outflow perspective views,respectively, of a surgical heart valve before coupling with an inflowanchoring skirt to form the prosthetic heart valve of the presentapplication;

FIG. 13 is an exploded assembly view of a portion of a cloth-coveredanchoring skirt for coupling to the surgical heart valve;

FIG. 14 is an exploded assembly view of the portion of the cloth-coveredanchoring skirt shown in FIG. 13 and a lower sealing flange securedthereto to form the inflow anchoring skirt;

FIG. 15A shows the surgical heart valve above the cloth-coveredanchoring skirt and schematically shows one method of coupling the twoelements, while FIG. 15B illustrates an inner plastically-expandablestent frame of the anchoring skirt and the pattern of coupling suturespassed therethrough;

FIGS. 16A-16J are perspective cutaway views of an aortic annulus showinga portion of the adjacent left ventricle below the ascending aorta, andillustrating a number of steps in deployment of an exemplary prostheticheart valve disclosed herein, namely:

FIG. 16A shows a preliminary step in preparing an aortic annulus forreceiving the heart valve including installation of guide sutures;

FIG. 16B shows the heart valve mounted on a distal section of a deliveryhandle advancing into position within the aortic annulus along the guidesutures;

FIG. 16C shows the heart valve in a desired implant position at theaortic annulus, and during placement of suture snares;

FIG. 16D shows forceps bending outward upper ends of the suture snaresto improve access to the heart valve and implant site;

FIG. 16E shows a delivery system prior to advancement of a dilatationballoon;

FIG. 16F shows the delivery system after advancement of a dilatationballoon therefrom;

FIG. 16G shows the balloon of the balloon catheter inflated to expandthe anchoring skirt;

FIG. 16H shows the balloon deflated and stretched;

FIG. 16I shows decoupling and removal of the balloon catheter from thevalve holder after removal of the snares;

FIG. 16J shows the fully implanted prosthetic heart valve with the guidesutures knotted on the proximal face of a sewing ring;

FIG. 17 is a perspective view showing the exemplary prosthetic heartvalve coupled to the valve holder along with components of a storagejar;

FIG. 18 is a perspective view of the heart valve and holder assembled toa storage clip that fits within the storage jar;

FIG. 18A is a bottom plan view of the valve holder mounted within thestorage clip;

FIG. 19A is a perspective view showing a balloon introducer sleeve onthe end of a handling rod being inserted through an inflow end of theprosthetic heart valve mounted in the storage clip within the storagejar (in phantom);

FIG. 19B shows the assembly of the heart valve/holder and storage clipbeing removed from the storage jar using the handling rod after couplingthe balloon introducer sleeve to the valve holder;

FIG. 19C shows the heart valve and holder being removed laterally fromwithin the storage clip;

FIG. 20 is a perspective exploded view of the balloon introducer sleeveand handling rod;

FIGS. 21A-21E are various views showing details of the balloonintroducer sleeve;

FIG. 22 is an exploded perspective view of components of a prostheticheart valve delivery system of the present application;

FIG. 23 is an assembled perspective view of the prosthetic heart valvedelivery system of FIG. 22;

FIGS. 24A-24C illustrate several steps in coupling the delivery systemof FIG. 23 to the prosthetic heart valve/holder assembly mounted on theend of the handling rod shown in FIG. 19C;

FIGS. 25 and 25A are perspective and longitudinal sectional views of alocking sleeve of the exemplary heart valve delivery system;

FIGS. 26 and 26A-26B are perspective, end, and longitudinal sectionalviews of an adapter of the heart valve delivery system that couples tothe heart valve holder;

FIG. 27 is a longitudinal sectional view taken along line 27-27 of FIG.24C showing the manner in which the adapter and locking sleeve couple tothe heart valve holder and balloon introducer sleeve;

FIG. 28 is a perspective view showing the heart valve/holder assemblymounted on the end of the delivery system with the handling rod removed,and illustrating the malleable nature of an elongated handle shaft ofthe delivery system;

FIG. 29 is a schematic perspective view of advancement of the heartvalve/holder assembly on the end of the delivery system toward a targetaortic annulus, again illustrating the advantageous malleability of theelongated delivery system handle shaft;

FIGS. 30 and 30A are elevational and broken longitudinal sectionalviews, respectively, of the heart valve delivery system with a ballooncatheter in a retracted position;

FIGS. 31 and 31A are elevational and broken longitudinal sectionalviews, respectively, of the heart valve delivery system with the ballooncatheter in an extended position;

FIG. 32 is a perspective view of the proximal end of the exemplary heartvalve delivery system of the present application showing a locking clipexploded therefrom, while FIGS. 33A and 33B are elevational and brokenlongitudinal sectional views, respectively, of the heart valve deliverysystem with a balloon catheter held in the retracted position by thelocking clip;

FIGS. 34-36 are views of an alternative embodiment for preventingpremature deployment of the balloon catheter in the valve deliverysystem using a toggle lever;

FIGS. 37A-37C are perspective views illustrating deployment of theballoon catheter through the prosthetic heart valve and expansion of theballoon to expand the anchoring skirt, analogous to FIGS. 16E-16G;

FIG. 38 is a partial sectional view of the heart valve delivery systemhaving the prosthetic heart valve and valve holder thereon and in theballoon advanced configuration of FIG. 31A;

FIG. 39 is a partial sectional view similar to FIG. 38 and showingmovement of a balloon extension wire to compress a spring upon ballooninflation;

FIG. 40 is similar to FIG. 38 and shows return movement of the balloonextension wire and spring upon balloon deflation;

FIGS. 41, 42 and 42A are perspective and sectional views of an exemplarystepped balloon construction used in the valve delivery system disclosedherein;

FIGS. 43, 44A-44D, and 45A-45C are external and sectional views of adistal end of a balloon extension wire and molded distal tip of theexemplary balloon catheter;

FIGS. 46A and 46B are views of exemplary prosthetic heart valvedisclosed herein, shown respectively assembled and with an expandableskirt exploded from a valve component;

FIGS. 47A-47B and 48A-48B are views of the exemplary prosthetic heartvalve schematically showing methods for crimping the expandable skirtinto a conical delivery configuration;

FIGS. 49A-49D and 50A-50E schematically illustrate an alternative systemincluding mechanical fingers for expanding the skirt stent of theprosthetic heart valve disclosed herein;

FIGS. 51, 52A-52C, 53, and 54A-54C schematically illustrate alternativevalve systems for fluid used to inflate the balloon on the catheterdisclosed herein that prevent premature deployment of the balloon;

FIG. 55 is a perspective view of an exemplary prosthetic heart valvehaving a commercially available valve components coupled with a skirtstent minus a surrounding fabric cover, and FIG. 55A is a radialsectional view through a cusp portion of the heart valve with the fabriccover of the skirt stent shown;

FIG. 56 is an exploded elevational view of the prosthetic heart valve ofFIG. 55;

FIG. 57 is a perspective view of an alternative prosthetic heart valvesimilar to that shown in FIG. 55 but having a different firmer sewingring; and

FIGS. 58A and 58B are radial sectional views through the prostheticheart valve of FIG. 57 illustrating alternative constructions.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention attempts to overcome drawbacks associated withconventional, open-heart surgery, while also adopting some of thetechniques of newer technologies which decrease the duration of thetreatment procedure. The prosthetic heart valves of the presentinvention are primarily intended to be delivered and implanted usingconventional surgical techniques, including the aforementionedopen-heart surgery. There are a number of approaches in such surgeries,all of which result in the formation of a direct access pathway to theparticular heart valve annulus. For clarification, a direct accesspathway is one that permits direct (i.e., naked eye) visualization ofthe heart valve annulus. In addition, it will be recognized thatembodiments of the prosthetic heart valves described herein may also beconfigured for delivery using percutaneous approaches, and thoseminimally-invasive surgical approaches that require remote implantationof the valve using indirect visualization. However, the latter twoapproaches—percutaneous and minimally-invasive—invariably rely oncollapsible/expandable valve constructs. And, while certain aspectsdescribed herein could be useful for such valves and techniques, theprimary focus and main advantages of the present application is in therealm of non-expandable “surgical” valves introduced in conventionalmanners.

One primary aspect of the present invention is a “unitary” prostheticheart valve in which a tissue anchor is implanted at the same time as avalve member resulting in certain advantages. The exemplary unitaryprosthetic heart valve of the present invention is a hybrid valvemember, if you will, with both non-expandable and expandable portions.By utilizing an expandable anchoring skirt or stent coupled to anon-expandable valve member, the duration of the anchoring operation isgreatly reduced as compared with a conventional sewing procedureutilizing an array of sutures. The expandable anchoring skirt may simplybe radially expanded outward into contact with the implantation site, ormay be provided with additional anchoring means, such as barbs. Asstated, conventional open-heart approach and cardiopulmonary bypassfamiliar to cardiac surgeons are used. However, due to the expandableanchoring skirt, the time on bypass is greatly reduced by the relativespeed of implant in contrast to the previous time-consuming knot-tyingprocess.

For definitional purposes, the terms “stent” or “coupling stent” referto a structural component that is capable of anchoring to tissue of aheart valve annulus. The coupling stents described herein are mosttypically tubular stents, or stents having varying shapes or diameters.A stent is normally formed of a biocompatible metal frame, such asstainless steel or Nitinol. More preferably, in the context of thepresent invention the stents are made from laser-cut tubing of aplastically-expandable metal. Other coupling stents that could be usedwith valves of the present invention include rigid rings, spirally-woundtubes, and other such tubes that fit tightly within a valve annulus anddefine an orifice therethrough for the passage of blood. It is entirelyconceivable, however, that the coupling stent could be separate clampsor hooks that do not define a continuous periphery. Although suchdevices sacrifice some contact uniformity, and speed and ease ofdeployment, they could be configured to work in conjunction with aparticular valve member.

A distinction between self-expanding and balloon-expanding stents existsin the field. A self-expanding stent may be crimped or otherwisecompressed into a small tube and possesses sufficient elasticity tospring outward by itself when a restraint such as an outer sheath isremoved. In contrast, a balloon-expanding stent is made of a materialthat is substantially less elastic, and indeed must be plasticallyexpanded from the inside out when converting from a contracted to anexpanded diameter. It should be understood that the termballoon-expanding stents encompasses plastically-expandable stents,whether or not a balloon is used to actually expand it (e.g., a devicewith mechanical fingers could expand the stent). The material of thestent plastically deforms after application of a deformation force suchas an inflating balloon or expanding mechanical fingers. Consequently,the term “balloon-expandable stent” should be understood as referring tothe material or type of the stent as opposed to the specific expansionmeans.

The term “valve member” refers to that component of a heart valve thatpossesses the fluid occluding surfaces to prevent blood flow in onedirection while permitting it in another. As mentioned above, variousconstructions of valve members are available, including those withflexible leaflets and those with rigid leaflets, or even a ball and cagearrangement. The leaflets may be bioprosthetic, synthetic, metallic, orother suitable expedients. In a preferred embodiment, the non-expandablevalve member is an “off-the-shelf” standard surgical valve of the typethat has been successfully implanted using sutures for many years, suchas the Carpentier-Edwards PERIMOUNT Magna® Aortic Heart Valve availablefrom Edwards Lifesciences of Irvine, Calif., though the autonomousnature of the valve member is not absolutely required. In this sense, a“off-the-shelf” prosthetic heart valve is suitable for stand-alone saleand use, typically including a non-expandable, non-collapsible supportstructure having a sewing ring capable of being implanted using suturesthrough the sewing ring in an open-heart, surgical procedure.

A primary focus of the present invention is a prosthetic heart valvehaving a single stage implantation in which a surgeon secures a hybridvalve having an anchoring skirt and valve member to a valve annulus asone unit or piece (e.g., a “unitary” valve). Certain features of thehybrid anchoring skirt and valve member are described in co-pending U.S.Patent Publication No. 2010-0161036, filed Dec. 10, 2009, the contentsof which are expressly incorporated herein. It should be noted that“two-stage” prosthetic valve delivery disclosed in the aforementionedpublication refers to the two primary steps of a) anchoring structure tothe annulus, and then b) connecting a valve member, which does notnecessarily limit the valve to just two parts. Likewise, the valvedescribed herein is especially beneficial in a single stage implantprocedure, but that does not necessarily limit the overall system tojust one part. For instance, the heart valve disclosed herein could alsouse an expanding base stent which is then reinforced by the subsequentlyimplanted heart valve. Because the heart valve has a non-expandable andnon-collapsible annular support structure, and a plastically-expandableanchoring skirt, it effectively resists recoil of a self-expanded basestent. That said, various claims appended hereto may exclude more thanone part.

As a point of further definition, the term “expandable” is used hereinto refer to a component of the heart valve capable of expanding from afirst, delivery diameter to a second, implantation diameter. Anexpandable structure, therefore, does not mean one that might undergoslight expansion from a rise in temperature, or other such incidentalcause such as fluid dynamics acting on leaflets or commissures.Conversely, “non-expandable” should not be interpreted to meancompletely rigid or a dimensionally stable, as some slight expansion ofconventional “non-expandable” heart valves, for example, may beobserved.

In the description that follows, the term “body channel” is used todefine a blood conduit or vessel within the body. Of course, theparticular application of the prosthetic heart valve determines the bodychannel at issue. An aortic valve replacement, for example, would beimplanted in, or adjacent to, the aortic annulus. Likewise, a mitralvalve replacement will be implanted at the mitral annulus. Certainfeatures of the present invention are particularly advantageous for oneimplantation site or the other, in particular the aortic annulus.However, unless the combination is structurally impossible, or excludedby claim language, any of the heart valve embodiments described hereincould be implanted in any body channel.

A “quick-connect” aortic valve bio-prosthesis described herein is asurgically-implanted medical device for the treatment of aortic valvesteno sis. The exemplary quick-connect device comprises an implantablebio-prosthesis and a delivery system for its deployment. The device,delivery system and method of use take advantage of the provenhemodynamic performance and durability of existing commerciallyavailable, non-expandable prosthetic heart valves, while improving easeof use and reducing total procedure time. This is mainly accomplished byeliminating the need to suture the bio-prosthesis onto the nativeannulus as is currently done per standard surgical practice, andtypically requires 12-24 manually-tied sutures around the valveperimeter. Also, the technique may obviate the need to excise theleaflets of the calcified valve and debride or smooth the valve annulus.

FIGS. 5A and 5B show an exemplary hybrid prosthetic heart valve 20 ofthe present application assembled on a valve holder 22, while FIGS. 6Aand 6B show the valve holder 22 separated from the heart valve 20. Asmentioned, the prosthetic heart valve 20 desirably includes a valvemember 24 having an anchoring skirt 26 attached to an inflow endthereof. The valve member 24 is desirably non-collapsible andnon-expandable, while the anchoring skirt 26 may expand from thecontracted state shown into an expanded state, as will be described. Inone embodiment, the valve member 24 comprises a Carpentier-EdwardsPERIMOUNT Magna® Aortic Heart Valve available from Edwards Lifesciencesof Irvine, Calif., while the anchoring skirt 26 includes an innerplastically-expandable frame or stent covered with fabric.

The valve holder 22, as seen in the details of FIGS. 6A and 6B, and alsoin FIGS. 7A-7D and 8A-8C, includes a central tubular hub portion 30having internal threads 31, and a plurality of stabilizing legs 32projecting axially and radially outward therefrom. Each of the threestabilizing legs 32 contacts and attaches to a cusp portion 34 of thevalve member 24 between commissure posts 35 (see FIG. 5A). An upper endof the hub portion 30 also has an internal star-shaped bore 36 thatprovides a valve-size-specific keyed engagement with a delivery system,as will be explained. Details of both the valve holder 22 and valvemember 24, and their interaction, will be provided below. Suffice it tosay at this point, that the valve holder 22 secures with sutures to thevalve member 24 from the time of manufacture to the time of implant, andis stored with the valve member.

In one embodiment, the holder 22 is formed of a rigid polymer such asDelrin polypropylene that is transparent to increase visibility of animplant procedure. As best seen in FIG. 8B, the holder 22 exhibitsopenings between the stabilizing legs 32 to provide a surgeon goodvisibility of the valve leaflets, and the transparency of the legsfurther facilitates visibility and permits transmission of lighttherethrough to minimize shadows.

FIGS. 7-8 also illustrate a series of through holes 37 in the legs 32permitting connecting sutures to be passed through fabric at the cusps34 of the prosthetic valve member 24 and across a cutting guide in eachleg. As is known in the art, severing a middle length of a suture thatis connected to the holder 22 and passes through the valve permits theholder to be pulled free from the valve when desired. Each leg 32extends radially outward and downward from the portion 30 in asubstantially constant thickness until a distal foot 38 which issubstantially wider. The distal foot 38 may be twice as wide as theupper portion of the respective leg 32. The through holes 37 passthrough circumferentially outer points of each distal foot 38, and arethus spaced significantly apart for each leg 32. This provides six totalattachment points between the holder 22 and the valve member 24, all inthe cusp regions 34. Moreover, each leg 32 extends down to the center ornadir of each cusp portion 34, which allows the surgeon better accessbehind and adjacent to the commissure posts. Furthermore, the spread outnature of the feet 38 and dual attachment points thereon provides anextremely robust holding force between the holder and bow. Theconfiguration of the wide feet 38 and through holes 37 thereon forms aninverted Y-shape of sorts. Prior holders either attached to the top ofthe commissure posts, or to a single point in the nadir of each cusp.Such holders left the valve prone to twisting or deforming from contactwith operating room or anatomical surfaces.

FIGS. 9-15 illustrate a number of steps in the construction of theprosthetic heart valve 20.

FIG. 9 illustrates an inner structural band subassembly 40 including aninner polymer band 42 having three upstanding posts 44 and a scallopedlower ring 46, and an outer more rigid band 48 having a scalloped shapeto conform to the lower ring 46. The band subassembly 40 is formed bypositioning the polymer band 42 within the rigid band 48 and securingthem together with sutures through aligned holes, for example.

FIG. 10 is a perspective view of a further subassembly of an undulatingcloth-covered wireform 50. FIG. 10A is a detailed sectional view of acusp portion of the wireform 50 showing an inner wire member 52 coveredwith fabric that defines a tubular portion 54 and an outwardlyprojecting flap 56. The wireform 50 defines three upstanding commissureposts 58 and three downwardly convex cusps 60. This is a standard shapefor tri-leaflet heart valves and mimics the peripheral edges of thethree native aortic leaflets. The shape of the wireform 50 coincideswith the upper edge of the band subassembly 40, and defines the outflowedge of the prosthetic valve 20. The band subassembly 40 and wireform 50are then joined together with a cloth interface and outer sewing ring,and then with flexible leaflets as will be shown.

FIG. 11 is a perspective view of the assembled band subassembly 40 andsewing ring 62, while FIG. 11A shows details through a cusp portionthereof. The two structural bands 42, 48 are the same heights in thecusp region and encompassed by a fabric cover 64 that is rolled into aperipheral tab 66. The sewing ring 62 comprises an inner suturepermeable member 68 having a frustoconical form and encompassed by asecond fabric cover 70. The two fabric covers 64, 70 are sewn togetherat a lower junction point 72.

FIGS. 12A and 12B are inflow and outflow perspective views,respectively, of the surgical heart valve member 24 before coupling withan inflow anchoring skirt to form the prosthetic heart valve 20.Although construction details are not shown, three flexible leaflets 74are secured along the undulating wireform 50 and then to the combinationof the band subassembly 40 and sewing ring 62 shown in FIG. 11. In apreferred embodiment, each of the three leaflets includes outwardlyprojecting tabs that pass through the inverted U-shaped commissure posts58 and wrap around the cloth-covered commissure posts 75 (see FIG. 11)of the band subassembly 40. The entire structure at the commissures iscovered with a secondary fabric to form the valve commissures 35 as seenin FIG. 15A.

As stated previously, the completed valve member 24 shown in FIGS. 12Aand 12B provides the occluding surfaces for the prosthetic heart valve20 described herein. Although an autonomous (i.e., capable ofstand-alone surgical implant) flexible leaflet valve member 24 isdescribed and illustrated, alternative valve members that have rigidleaflets, or are not fully autonomous may be substituted. In variouspreferred embodiments, the valve leaflets may be taken from anotherhuman heart (cadaver), a cow (bovine), a pig (porcine valve) or a horse(equine). In other preferred variations, the valve member may comprisemechanical components rather than biological tissue.

One feature of the valve member 24 that is considered particularlyimportant is the sewing ring 62 that surrounds the inflow end thereof.As will be seen, the sewing ring 62 is used to attach the anchoringskirt 26 to the valve member 24. Moreover, the sewing ring 62 presentsan outward flange that contacts and outflow side of the part of annulus,while the anchoring skirt 26 expands and contracts the opposite,ventricular side of the annulus, therefore securing the heart valve 20to the annulus from both sides. Furthermore, the presence of the sewingring 62 provides an opportunity for the surgeon to use conventionalsutures to secure the heart valve 20 to the annulus as a contingency.

The preferred sewing ring 62 defines a relatively planar upper oroutflow face and an undulating lower face. Cusps of the valve structureabut the sewing ring upper face opposite locations where the lower facedefines peaks. Conversely, the valve commissure posts align withlocations where the sewing ring lower face defines troughs. Theundulating shape of the lower face advantageously matches the anatomicalcontours of the aortic side of the annulus AA, that is, thesupra-annular shelf. The ring 62 preferably comprises a suture-permeablematerial such as rolled synthetic fabric or a silicone inner corecovered by a synthetic fabric. In the latter case, the silicone may bemolded to define the contour of the lower face and the fabric coverconforms thereover.

Now with reference to FIGS. 13 and 14, assembly of the cloth-coveredanchoring skirt 26 will be described. It should first be noted that thesize of the anchoring skirt 26 will vary depending on the overall sizeof the heart valve 20. Therefore the following discussion applies to allsizes of valve components, with the dimensions scaled accordingly.

The general function of the anchoring skirt 26 is to provide the meansto attach the prosthetic valve member 24 to the native aortic root. Thisattachment method is intended as an alternative to the present standardsurgical method of suturing aortic valve bio-prostheses to the aorticvalve annulus, and is accomplished in much less time. Further, thisattachment method improves ease of use by eliminating most of not allsuturing. The anchoring skirt 26 may be a pre-crimped, tapered, 316Lstainless steel balloon-expandable stent, desirably covered by apolyester fabric to help seal against paravalvular leakage and promotetissue ingrowth once implanted within the annulus. The anchoring skirt26 transitions between the tapered constricted shape of FIGS. 5A-5B toits flared expanded shape shown in FIG. 16J below.

The anchoring skirt 26 comprises an inner stent frame 80, a fabriccovering 82, and a band-like lower sealing flange 84. The inner stentframe 80 will be described in greater detail below, but preferablycomprises a tubular plastically-expandable member having an undulatingor scalloped upper end 86. The stent frame 80 assembles within a tubularsection of fabric 82 which is then drawn taut around the stent frame,inside and out, and sewn thereto to form the intermediate cloth-coveredframe 88 in FIG. 13. During this assembly process, the stent frame 80 isdesirably tubular, though later the frame will be crimped to a conicalshape as see in FIG. 15B for example. A particular sequence forattaching the tubular section of fabric 82 around the stent frame 80includes providing longitudinal suture markers (not shown) at 120°locations around the fabric to enable registration with similarlycircumferentially-spaced, commissure features on the stent frame. Aftersurrounding the stent frame 80 with the fabric 82, a series oflongitudinal sutures at each of the three 120° locations secure the twocomponents together. Furthermore, a series of stitches are providedalong the undulating upper end 86 of the stent frame 80 to complete thefabric enclosure. In one embodiment, the tubular section of fabric 82comprises PTFE cloth, although other biocompatible fabrics may be used.

Subsequently, the lower sealing flange 84 shown in FIG. 14 is attachedcircumferentially around a lower edge of the intermediate cloth-coveredframe 88. First, a linear band 90 of a single layer of fabric,preferably knitted, is formed into a ring and its ends sutured togetherusing a butt joint (not shown). The ring is placed around theintermediate cloth-covered frame 88, aligned with a lower edge thereof,and sewn thereto. Preferably, a series of stitches are formed at andadjacent to the commissure markers previously described. Alternatively,two circumferential lines of stitches may be provided around the lowersealing flange 84 to provide greater anchoring.

The material of the lower sealing flange 84 may vary, but preferablyprovides a compressible flange about the lower edge of the anchoringskirt 26. For example, the lower sealing flange 84 may be a knitted PTFEfabric in a single layer or multiple layers, Teflon, a silicone ringcovered by fabric, or other similar expedients. Furthermore, the sealingflange 84 may not comprise fabric at all, but may be a hydrophiliccoating, fibrin glue, or other such substance that helps prevent leakagearound the outside of the anchoring skirt 26. The main functions of thefabric layers covering the frame 88 are to help prevent paravalvularleaks and provide means to securely encapsulate any Calcium nodules onthe aortic valve leaflets (if left in place) and/or the aortic valveannulus. Covering the entire anchoring skirt 26 eliminates exposed metaland decreases the risk of thromboembolic events and abrasion. In apreferred embodiment, the sealing flange 84 has an axial dimension ofbetween about 2-5 mm, and is spaced from the upper end 86 of the frame80 by a distance that varies between 2-5 mm. The lower end of the framemay also be scalloped to follow the upper end 86, in which case thesealing flange 84 may also undulate to maintain an even distance withthe upper end 86. If a knitted PTFE fabric, the sealing flange 84desirably has a radial thickness of at least twice the thickness of thetubular fabric 82.

FIG. 15A shows the surgical heart valve member 24 above thecloth-covered anchoring skirt 26 and one way to couple the two elementsusing sutures. FIG. 15B illustrates the inner stent frame 80 with clothcovering removed to indicate a preferred pattern of coupling suturespassed therethrough.

The anchoring skirt 26 preferably attaches to the sewing ring 62 duringthe manufacturing process in a way that preserves the integrity of thering and prevents reduction of the valve's effective orifice area (EOA).Desirably, the anchoring skirt 26 will be continuously sutured to thering 62 in a manner that maintains the contours of the ring. In thisregard, sutures may be passed through apertures or eyelets 92 arrayedalong the upper or first end 86 of the inner stent frame 80. Otherconnection solutions include prongs or hooks extending inward from thestent, ties, Velcro, snaps, adhesives, etc. Alternatively, the anchoringskirt 26 may be more rigidly connected to rigid components within theprosthetic valve member 24.

The inner stent frame 80 is seen in greater detail in FIGS. 13 and 15B.The inner stent frame 80 may be similar to an expandable Stainless Steelstent used in the Edwards SAPIEN Transcatheter Heart Valve. However, thematerial is not limited to Stainless Steel, and other materials such asCo—Cr alloys, etc. may be used. Ultimately, the inner stent frame 80assumes a crimped, tapered configuration that facilitates insertionthrough the calcified native aortic valve (see FIG. 7A). In the taperedconfiguration, a lower edge 94 of the frame 80 describes a circle havinga smaller diameter than a circle described by the upper end 86. Theupper end 86 follows an undulating path with alternating arcuate troughsand pointed peaks that generally corresponds to the undulating contourof the underside of the sewing ring 62 (see FIG. 5B). The mid-section ofthe frame 80 has three rows of expandable struts 98 in a sawtoothpattern between axially-extending struts 100. The axially-extendingstruts 100 are out-of-phase with the peaks and troughs of the upper end86 of the stent. The reinforcing ring defined by the thicker wire upperend 86 is continuous around its periphery and has a substantiallyconstant thickness or wire diameter interrupted by the aforementionedeyelets 92. Note that the attachment sutures ensure that the peaks ofthe upper end 86 of the skirt 26 fit closely to the troughs of thesewing ring 62, which are located under the commissures of the valve.

The minimum I.D. of the upper end 86 of the covered skirt 26 will alwaysbe bigger than the I.D. of the prosthetic valve member 24 to which itattaches. For instance, if the upper end 86 secures to the underside ofthe sewing ring 62, which surrounds the support structure of the valve,it will by definition be larger than the I.D. of the support structure(which defines the valve orifice and corresponding labeled valve size).

An exemplary implant procedure for the prosthetic heart valve 20 willnow be described with reference to FIGS. 16A-16J, which are sectionalviews through an isolated aortic annulus AA showing a portion of theadjacent left ventricle LV and ascending aorta AO with sinus cavities.The two coronary arteries CA are also shown. As will be explained, theanchoring skirt 26 is deployed against the native leaflets or, if theleaflets are excised, against the debrided aortic annulus AA as shown.

In the ensuing procedure drawings, the heart valve 20 is oriented withan inflow end down and an outflow end up. Therefore, the terms inflowand down may be used interchangeably at times, as well as the termsoutflow and up. Furthermore, the terms proximal and distal are definedfrom the perspective of the surgeon delivering the valve inflow endfirst, and thus proximal is synonymous with up or outflow, and distalwith down or inflow.

An implant procedure involves delivering the heart valve 20 andexpanding the anchoring skirt 26 at the aortic annulus. Because thevalve member 24 is non-expandable, the entire procedure is typicallydone using the conventional open-heart technique. However, because theanchoring skirt 26 is implanted by simple expansion, with reducedsuturing, the entire operation takes less time. This hybrid approachwill also be much more comfortable to surgeons familiar with theopen-heart procedures and commercially available heart valves.

Moreover, the relatively small change in procedure coupled with the useof proven heart valves should create a much easier regulatory path thanstrictly expandable, remote procedures. Even if the system must bevalidated through clinical testing to satisfy the Pre-Market Approval(PMA) process with the FDA (as opposed to a 510 k submission), at leastthe surgeon acceptance of the quick-connect heart valve 20 will begreatly streamlined with a commercial heart valve that is alreadyproven, such as the Magna® Aortic Heart Valve.

FIG. 16A shows a preliminary step in preparing an aortic annulus AA forreceiving the heart valve 20, including installation of guide sutures102. The aortic annulus AA is shown schematically isolated and it shouldbe understood that various anatomical structures are not shown forclarity. The annulus AA includes a fibrous ring of tissue that projectsinward from surrounding heart walls. The annulus AA defines an orificebetween the ascending aorta AO and the left ventricle LV. Although notshown, native leaflets project inward at the annulus AA to form aone-way valve at the orifice. The leaflets may be removed prior to theprocedure, or left in place as mentioned above. If the leaflets areremoved, some of the calcified annulus may also be removed, such as witha rongeur. The ascending aorta AO commences at the annulus AA with threeoutward bulges or sinuses, two of which are centered at coronary ostia(openings) CO leading to coronary arteries CA. As will be seen below, itis important to orient the prosthetic valve member 24 so that itscommissure posts are not aligned with and thus not blocking the coronaryostia CO.

The surgeon attaches the guide sutures 102 at three evenly spacedlocations around the aortic annulus AA. In the illustrated embodiment,the guide sutures 102 attach to locations below or corresponding to thecoronary ostia CO (that is, two guide sutures are aligned with theostia, and the third centered below the non-coronary sinus). The guidesutures 102 are shown looped twice through the annulus AA from theoutflow or ascending aorta side to the inflow or ventricular side. Ofcourse, other suturing methods or pledgets may be used depending onsurgeon preference.

FIG. 16B shows the guide sutures 102 having been secured so that eachextends in pairs of free lengths from the annulus AA and out of theoperating site. The heart valve 20 mounts on a distal section of adelivery system 110 and the surgeon advances the valve into positionwithin the aortic annulus AA along the guide sutures 102. That is, thesurgeon threads the three pairs of guide sutures 102 through evenlyspaced locations around the sewing ring 62. If the guide sutures 102, asillustrated, anchor to the annulus AA below the aortic sinuses, theythread through the ring 62 mid-way between the valve commissure posts.Thus, the guide sutures 102 pass through the sewing ring 62 at the cuspsof the valve and are less likely to become tangled with the valvecommissure posts. Furthermore, the exemplary ring 62 has an undulatinginflow side such that the cusp locations are axially thicker than thecommissure locations, which provides more material for securing theguide sutures 102.

FIG. 16C shows the heart valve in a desired implant position at theaortic annulus AA, and during placement of tubular suture snares. Thesewing ring 62 is positioned supra-annularly, or above the narrowestpoint of the aortic annulus AA, so as to allow selection of a largerorifice size than a valve placed intra-annularly. Furthermore, withannulus expansion using the anchoring skirt 26, and the supra-annularplacement, the surgeon may select a valve having a size one or twoincrements larger than previously conceivable. A dilatation balloon 112on the delivery system 110 can be seen just beyond the distal end of theanchoring skirt 26.

The surgeon delivers a plurality of suture snares 120 down each freelength of the guide sutures 102 into contact with the upper or outflowside of the sewing ring 62. The snares 120 enable downward pressure tobe applied to the ring 62 and thus the valve 20 during the implantprocedure, which helps insure good seating of the ring 62 on the annulusAA. The snares 120 also provide rigid enclosures around each of theflexible guide sutures 102 which helps avoid entanglement with othermoving surgical instruments, as will be appreciated. As there are threepairs of guide sutures 102 (six free lengths) three snares 120 areutilized, though more or less is possible. The snares 120 are typicallytubular straw-like members of medical grade plastic.

FIG. 16D shows forceps 122 clamping upper ends of the suture snares 120,and bending one pair outward to improve access to the heart valve 20 andimplant site.

FIG. 16E shows all of the pairs of suture snares 120 bent outward and amajority of the delivery system 110. Although it will be described ingreater detail below, the delivery system 110 includes a malleablehandle shaft 130 for manipulating the heart valve 20 on the holder 22.The delivery system 110 is in a configuration prior to advancement ofthe dilatation balloon 112.

FIG. 16F shows the delivery system after advancement of the dilatationballoon 112. The balloon 112 projects downward through the valve 20, andinto the left ventricle. As will be explained below, the delivery system110 provides binary position displacement of the balloon 112, eitherretracted substantially within the handle shaft 130 or advancedprecisely as far as necessary to expand the anchoring skirt 26 of theprosthetic heart valve 20.

FIG. 16G shows the dilatation balloon 112 inflated to expand theanchoring skirt 26 against the ventricular side of the aortic annulus.The balloon 112 desirably has a frustoconical profile that expands theanchoring skirt 26 into a frustoconical expanded state. Not only doesthis conform better to the subannular contours but over expands somewhatthe annulus that a larger valve maybe utilized then without theexpansion. One advantage of using a plastically-expandable stent is theability to expand the native annulus to receive a larger valve size thanwould otherwise be possible with conventional surgery. Desirably, theleft ventricular outflow tract (LVOT) is significantly expanded by atleast 10%, or for example by 1-5 mm, and the surgeon can select a heartvalve 20 with a larger orifice diameter relative to an unexpandedannulus. Even a 1 mm increase in annulus size is significant since thegradient is considered to be proportional to the radius raised to the4^(th) power.

The balloon 112 desirably is tapered to have an angle between about0-45°, and more preferably is about 38° (0° being a cylindricalexpansion). Alternatively, the balloon 112 may include curves ornon-axi-symmetric contours to deform the anchoring skirt 26 to variousdesired shapes to fit better within the particular annulus. Indeed,various potential shapes are described in U.S. Patent Publication2008-0021546, entitled System for Deploying Balloon-Expandable HeartValves, published Jan. 24, 2008, the disclosure of which is expresslyincorporated herein.

FIG. 16H then illustrates the balloon 112 deflated and rewrapped. Aspring mechanism within the delivery system 110 along with longitudinalpleats in the balloon 112 facilitate rewrapping of the balloon whendeflated into an extremely narrow configuration which makes removaleasier.

FIG. 16I shows retraction of the balloon 112 and entire delivery system110 from the valve holder 22 before or after removal of the snares 120,which happens only as a contingency. Although not shown, the most commonprocedure after expansion of the balloon and skirt 26 involves thesurgeon severing the connecting sutures between the valve holder 22 andthe prosthetic valve member 24, and removing the entire delivery system.Severing a middle length of each suture that connects the holder 22 tothe valve member 24 permits the delivery system 110 with the holder atthe distal end to be pulled free from the valve 20. However, thedelivery system 110 also features a simple engagement and detachmentmechanism explained below that enables the surgeon to easily remove thesystem 110 from the holder 22 which remains attached to the valve 20, asseen in FIG. 16I. This detachment may be needed to replace the ballooncatheter, such as if the original balloon develops a leak or for somereason does not deploy properly. This “quick-release” arrangementpermits the surgeon to rapidly exchange catheters while leaving thevalve 20 in place.

Finally, FIG. 16J shows the fully implanted prosthetic heart valve 20with the guide sutures 102 knotted on the proximal face of a sewing ring62. The guide sutures 102 are primarily for rotationally orienting theheart valve 20 as it seats against the aortic annulus and to define aplane for axial positioning. As such, the guide sutures 102 are notbelieved strictly necessary for securing the heart valve 20 at theannulus. Moreover, although knots are shown for securing the guidesutures 102, other devices such as clips or cinches could be used tospeed up the process

Placement of the guide sutures 102 at the cusps of the native valve andprosthesis separates the knots from the commissures, thus increasingaccessibility. Also, the number of knots are reduced to three betweenthe commissure posts, rather than multiple knots (12-24) as before, someof which were behind the commissure posts. The use of three suturescorrectly positions the valve 20 and centering the sutures between thecommissure posts is the most accessible for tying knots because thecusps are the lowest points in the annulus. Placement of knots (orclips) at the lowest point in the annulus also helps minimize the riskof coronary occlusion.

FIG. 17 illustrates an exemplary arrangement of components for storingthe prosthetic heart valve 20 after manufacture and prior to use. This“wet” storage arrangement applies to the illustrated heart valve 20shown, which includes conventional bioprosthetic leaflets, but couldalso be used for bioprosthetic leaflets that have been dried and alsofor mechanical valves.

The heart valve 20 is shown attached to the aforementioned holder 22 andabove a storage clip 140 that fits within a storage jar 142 having a lid144. FIG. 18 illustrates the heart valve 20 and holder 22 mounted to thestorage clip 140. The inflow end of the heart valve 20, and inparticular the expandable anchoring skirt 26, faces upward in thismounting arrangements. This orientation enables a technician to insert ahandling rod and leaflet parting sleeve described below through thecenter of the heart valve 20 from the inflow to the outflow side.Typically, prosthetic aortic valves are stored with the outflow side andcommissures pointed upward so that a handle may be attached to anupstanding holder, as this is the standard delivery orientation.

If the prosthetic heart valve 20 has conventional bioprostheticleaflets, they require a liquid preservative for long-term storage.Therefore, a preservative such as glutaraldehyde is provided within thejar 142.

FIG. 18A is a bottom view of the valve holder 22 mounted within thestorage clip 140 which illustrates, along with FIG. 18, structure thatindicates to an assembler that the two components are not properlyengaged. More particularly, with reference back to FIG. 6A, the centraltubular hub portion 30 of the holder 22 features a plurality ofoutwardly projecting tabs or lugs on three evenly-spaced sides forengaging the storage clip 140. On two of the sides, as shown, theseinclude a small lug 150 on the outflow end of the holder spaced from alonger lug 152 across a gap. On the third side, as best seen in FIG. 18,a single elongated lug 154 extends the length of the central hub portion30. The gaps between the lugs 150, 152 receive the inner edges of acentral aperture of the storage clip 140, while the elongated lug 154extends out through a lateral exit slot 156. Because the elongated lug154 is uninterrupted, if an assembler inserts the holder 22 into thecentral aperture of the storage clip 140 in other than the orientationshown, the lug 154 will wedge apart the two semi-circular side of thestorage clip 140 and prevent the clip from fitting within the storagejar 142.

FIGS. 19A-19C illustrate several steps in removal of the prostheticheart valve 20 from the storage jar 142. A user grasps a handling rod160 having a balloon introducer sleeve 162 mounted on a distal endthereof. The balloon introducer sleeve 162, shown in more detail inFIGS. 21A-21E, includes external threads 164 that engage the internalthreads 31 on the valve holder 22. Inserting the sleeve 162 through thevalve 20 from the inflow side, the user screws the sleeve into theholder 22. The prosthetic heart valve 20 attached to the holder 22 canthen be removed from the jar 142, which also removes the storage clip140, as seen in FIG. 19B. FIG. 19C shows the user detaching the valveholder 22 from the storage clip 140 by pulling it laterally through theexit slot 156 (FIG. 18A).

Attachment of the introducer sleeve 162 in this manner provides severalbenefits. First and foremost, the sleeve 162 defines a throughbore atthe level of the valve leaflets 74 for passage of a balloon catheterfrom the outflow side. Typically three valve leaflets 74 span theorifice defined by the valve support structure and have free edges thatcome together or “coapt” generally along three line segments oriented120° apart that intersect at the centerline. This configuration mimics anative valve and performs well in permitting blood flow in one directionbut not the other. Though extremely durable in use, the valve leaflets74 are relatively fragile and susceptible to damage from contact withsolid objects during the implant procedure, especially if they are madefrom bioprosthetic tissue such as bovine pericardium or a porcinexenograft. Consequently, the introducer sleeve 162 parts the leaflets 74and provides a protective barrier between them and a balloon catheterthat passes through the valve, as will be seen below. Without the sleeve162 a balloon catheter would have to force its way backward past thecoapted leaflet free edges. A further benefit of the parting sleeve 162is the ease with which it is assembled to the holder 22. Attachmentthrough the valve 20 to the holder 22 is intuitive, and removal of thehandling rod 160 simple. The valve 20 and holder 22 assembly are storedtogether prior to use, often in a storage solution of glutaraldehyde orother preservative. The introducer sleeve 162 is preferably notpre-attached to the holder 22 to avoid causing any indentations in theleaflets 74 from long-term contact therewith. That is, the leaflets 74are stored in their relaxed or coapted state.

At this stage, the user can easily rinse off the storage solution fromthe prosthetic heart valve 20 while it remains on the end of handlingrod 160. Furthermore, and as will be explained below, handling rod 160provides a convenient tool for positioning the heart valve 20 and holder22 for engagement with the delivery system 110. Prior to a detailedexplanation of this engagement, and the delivery system components,better understanding of the configuration and function of the balloonintroducer sleeve 162 is necessary.

FIG. 20 shows the balloon introducer sleeve 162 exploded from thehandling rod 160. The handling rod 160 includes an elongated preferablytubular linear handle terminating in a circular flange 166 just before adistal end 168 having a substantially star-shaped outer profile.

The balloon introducer sleeve 162 as seen in FIG. 21A-21E issubstantially tubular and includes an enlarged first end 170 having aninternal bore with a star-shaped profile that matches the externalstar-shaped profile of the distal end 168 of the handling rod 160.Indeed, the distal end 168 of handling rod 160 fits snugly within thefirst end 170 of the sleeve 162 up to the circular flange 166. FIGS. 21Dand 21E illustrate a circular groove 172 formed just within the mouth ofthe first end 170 that is sized to receive a similarly shaped rib (notshown) provided on the distal end 168 of handling rod 160. Engagementbetween the rib and the circular groove 172 provides a suitableinterference between the two components that prevents their detachmentup until application of a threshold longitudinal separating force. Thisseparating force is larger than the combined weight of the heart valve20, holder 22, and storage clip 140, but small enough so that a user caneasily pull them apart. It should be noted that the alternating ribs andchannels of the respective star-shaped male and female components aretapered toward their engaging ends so that they can be rapidly connectedeven with some misalignment.

The tubular sleeve 162 includes the aforementioned external threads 164adjacent to the enlarged first end 170, and has a substantially constantouter diameter to a second end 174 except for a circular groove 176. Theinner lumen of the sleeve 162 extends away from the first end 170 for ashort distance in a constant diameter portion 180, and then includes anarrowing taper 182 leading to a second constant diameter portion 184that extends to the second end 174. The functional advantages of thesesurfaces, along with the overall purpose of the sleeve 162 will bedescribed below.

FIG. 22 is an exploded view of the prosthetic heart valve deliverysystem 110, while FIG. 23 shows the system assembled. Although notshown, a balloon protector sleeve will be place around the balloon 112for protection during shipping. The protector sleeve is a tubularcomponent with a flared distal end, the diameter of which is larger thanthe ID of the introducer lumen to ensure the balloon protector isremoved prior to connection of the two components. On its proximal end,the system 110 includes an end cap 190 having a luer adapter 192, aballoon extension spring 194, a spring compression pin 196, a balloondisplacer 198, an inflation tube 199, and a balloon extension wire 200.In mid-portion of the system 110 includes a centering washer 202, ahandpiece 204, and the aforementioned malleable handle shaft 130.Finally, distal components of the system 110 include a tubular lockingsleeve 206, a valve holder adapter 208, the dilatation balloon 112, andan insert molded tip 210. The entire system preferably has a length fromthe proximal end of the luer adapter 192 to the balloon wire tip 210 ofbetween about 100 and 500 mm.

FIG. 23 shows the end cap 190 and balloon displacer 198 joined together,preferably with adhesive or other such coupling means. The assembly ofthe end cap 190 and balloon displacer 198 may be displaced linearly withrespect to the handpiece 204. The malleable handle shaft 130 extendsdistally from the handpiece 204 and is preferably secured thereto withadhesive or the like. The valve holder adapter 208 fixes to a distal endof the handle shaft 130, but the locking sleeve 206 slides over thehandle.

One aspect of the present application that is quite significant is theintegration of a balloon catheter per se within the delivery system 110.Namely, previous systems for delivering prosthetic heart valves in thismanner have included separate introducer and balloon catheter elements,where the balloon catheter inserts through the tubular introducer.Although such a system may work suitably for its intended purpose, anintegrated balloon catheter within the delivery system 110 providesdistinct advantages. First of all, if there is a problem with theballoon, such as a puncture, the surgeon need not retract the entireballoon catheter through the introducer and introduce another one, whichis time consuming. Instead, the delivery system 110 is merely decoupledfrom the valve holder 22, and a replacement delivery system 110 engagedto the holder. Secondly, and perhaps more evident, a single deliverysystem 110 replacing multiple parts speeds up the entire process andfacilitate ease-of-use. The surgeon no longer has to couple multipleparts together prior to attaching to the heart valve holder, ormanipulate a separate balloon catheter relative to an introducer tube.Sliding a balloon catheter through an elongated introducer opens up therisk of snags and balloon tears. Finally, the amount of packaging isreduced accordingly.

FIGS. 24A-24C illustrate several steps in coupling the delivery system110 to the prosthetic heart valve 20 and holder 22 assembly that is heldon the end of the handling rod 160. As explained above, the balloonintroducer sleeve 162 threads within the holder 22. A portion of thesleeve 162 terminating in the second end 174 projects out from withinthe holder 22 and presents a tubular entryway for the balloon wire tip210 and balloon 112, as seen in FIG. 24A. The user inserts the deliverysystem 110 through the introducer sleeve 162 until a distal shoulder 212of the valve holder adapter 208 contacts the holder 22.

FIGS. 25 and 25A show details of the locking sleeve 206, and FIGS. 26and 26A-26B illustrate the holder adapter 208. With reference inparticular to FIG. 26B, the adapter 208 includes an elongated throughbore 214 which receives the second end 174 of the introducer sleeve 162.A plurality of cantilevered fingers 216 extent longitudinally along theadapter 208, terminating at the distal end 212. Each of the fingers 216includes an inwardly directed bump 218. Sliding the adapter 208 over theintroducer sleeve 162 such that the distal shoulder 212 contacts aproximal face of the holder 22 brings the bumps 218 over the externalgroove 176 (see FIG. 21A).

FIGS. 24B and 24C show advancement of the locking sleeve 206 along theelongated handle shaft 130 and over the holder adapter 208. The finalconfiguration of FIG. 24C is also shown in section view in FIG. 27.Because the inner bore of the locking sleeve 206 fits closely around theadapter 208, the cantilevered fingers 216 are retained in their alignedorientation with the bumps 218 in the groove 176 of the sleeve 162. Thelocking sleeve 206 desirably frictionally engages the exterior of theadapter 208 to prevent two parts from easily coming apart.Alternatively, a separate detent or latch may be provided for moresecurity. Ultimately, when the locking sleeve 206 is in the position ofFIG. 24C, the delivery system 110 is securely coupled to the valveholder 22. Moreover, the balloon 112 extends through the balloonintroducer sleeve 162 and slightly out the inflow end of the expandableskirt 26.

Another advantageous feature of the present application is a keyedengagement between delivery systems 110 and holders 22 for the same sizeof heart valves. As seen previously in FIG. 6A, the hub portion 30 ofthe holder 22 has an internal star-shaped bore 36 which is sized andpatterned to be keyed to an external star-shaped rim 220 provided on theholder adapter 208 (see FIGS. 26A and 26B). Because the balloon catheteris integrated with the delivery system 110, and each balloon catheter issized for a particular valve, only the delivery system 110 which isdesigned for that particular valve should be coupled to its holder. Thatis, each expansion skirt 26 must be expanded to a particular diameter,which requires different sizes of balloons 112. Consequently, eachdifferently sized valve holder and a delivery system combination has aunique star-shaped pattern which prevents mating with a different size.

Typically, the delivery system is packaged separately from the heartvalve and holder, and this keying arrangement prevents misuse of thewrong delivery system. Additionally, if the balloon breaks and anotherdelivery system must be rapidly obtained and utilized, the keyingarrangement prevents the wrong delivery system from being substituted.There are typically 6-8 valve sizes in 2 millimeter increments, and thusa similar number of unique keyed couplings will be provided.Furthermore, the star-shaped pattern disclosed permits engagement at aplurality of rotational orientations. In a preferred embodiment, theuser must rotate the delivery system 110 no more than 30° before thestar-shaped rim 220 of the adapter 208 mates with the internalstar-shaped bore 36 of the holder 22. This is extremely beneficial ifchanging out the delivery system 110, because the original elongatedhandle shaft 130 may be bent into a particular orientation (see below)which is much easier to replicate if the keyed features do not have tobe oriented in only one or two angular relations.

FIG. 28 is a perspective view showing the assembly of the heart valve 20and holder 22 mounted on the end of the delivery system 110 with thehandling rod 160 removed. In a preferred embodiment, the elongatedhandle shaft 130 is malleable or bendable into various shapes. FIG. 29also shows the advantageous malleability of the elongated deliverysystem handle shaft 130. This bendability of the handle shaft 130significantly enhances the ability of a surgeon to correctly positionthe heart valve 20 as it advances toward the annulus. Often, accesspassageways into the heart during a surgical procedure are somewhatconfined, and may not provide a linear approach to the annulus.Accordingly, the surgeon bends the handle shaft 130 to suit theparticular surgery.

Various materials and constructions may be utilized to provide amalleable tube for use as the handle shaft 130. For example, a pluralityof Loc-Line connectors should be used which provide axial rigidity withbending flexibility. The handle shaft 130 must be axially rigid so thatit can position the heart valve in the annulus with confidence. Anotherexample is a plastic tube having a metal coil embedded therein toprevent kinking. In a preferred embodiment, an aluminum tube having achromate (e.g., Iridite) coating is used. Aluminum is particularlywell-suited for forming small tubes that can be bent without kinking,but should be coated with Iridite or the like to prevent deteriorationin and reaction with the body. A highly desirable feature of the handleshaft 130 is its resistance to recoil. Aluminum provides aninsignificant level of recoil that permits the surgeon to bend the shaft130 to conform to a particular patient's anatomy without worry that thehandle shaft will change its shape once bent. On the other hand, thoughstainless steel will be sufficient if it remains straight, any bendingwill be followed by recoil so that the surgeon cannot be assured of thefinal orientation of the shaft. As mentioned, Loc Line connectors maywork, but a solid shaft that is easy to sterilize is preferred.

The limit on recoil may be quantified by bending different materials andevaluating the force required to bend in conjunction with the amount ofrecoil. For these tests, the bend force is the peak force needed to bendthe malleable handle of a fully assembled delivery system to 90° with a1.5″ radius. The recoil is the degrees of recoil after the malleablehandle is bent as such. For instance, a 5° recoil means that the 90°bend angle recovered to a bend angle of 85°. A number of materials aresuitable for use as the delivery system handle shaft 130, in particularvarious biocompatible metals and alloys. Stainless steel (SS) has betterrecoil property than aluminum (Al), meaning it recoils less, yetrequires a much higher bend force due to its higher tensile property. ASS shaft handle will have to be relatively thin to reduce the forcerequired, and could be made with longitudinal slots to reduce the bendforce even more. However the cost of a SS handle with slots much morethan that of an Al handle. Al is preferred for its low recoil propensityand relative ease to bend it.

FIGS. 30 and 30A are elevational and broken longitudinal sectionalviews, respectively, of the heart valve delivery system 110 with aballoon 112 in a retracted position, while FIGS. 31 and 31A are similarviews with the balloon 112 extended. The balloon catheter of thedelivery system 110 has two binary longitudinal positions relative tothe handpiece 204 and its associated structures. In a retracted positionshown in FIGS. 30 and 30A, the connected end cap 190, balloon displacer198, inflation tube 199, and balloon 112 are retracted to the left withrespect to the handpiece 204. Note the spacing A between a distalshoulder 230 of the balloon displacer 198 and the centering washer 202within the handpiece 204. The balloon 112 resides partway within theholder adapter 208 in this position. Once the balloon catheter isdisplaced to the right, as seen in FIGS. 31 and 31A, the spacing Adisappears and the balloon 112 projects out from within the handleadapter 208.

The delivery system 110 provides an extremely accurate system forpositioning the balloon 112 relative to the heart valve, and inparticular the anchoring skirt 26. Because of the simple engagementbetween the handle adapter 208 and the handle shaft 130, very littletolerance errors are introduced. The handle adapter 208 is fixed to theelongated handle shaft 130, which in turn is fixed to the handpiece 204.Movement of the balloon catheter structures relative to the handpiece204 thus displaces the balloon 112 in a 1:1 correspondence with respectto the holder 22 and attached heart valve 20. Furthermore, a pair ofsmall resilient détentes 232 provided on the balloon displacer 198engage similarly sized cutouts 234 on the proximal end of the handpiece204. This locks the position of the balloon catheter with respect to thehandpiece 204, or in other words locks the position of the balloon 112with respect to the anchoring skirt 26.

The balloon inflation tube 199 and balloon extension wire 200 are formedof materials that have column strength but are relatively flexible inbending. As explained further below, the wire may be Nitinol while theinflation tube 199 is desirably formed of a braid reinforcedthermoplastic elastomer (TPE) such as a polyether block amide knownunder the tradename of PEBAX® (Arkema of Colombes, France).

As the delivery system 110 may be subjected to several bends in use,care must be taken to ensure that the concentric tubes and wire do notintroduce misalignment. That is, smaller diameter objects tend to travelshorter paths within larger concentric tubes, thus cause them to extendout of the distal end of the tubes after being bent. As such, theballoon inflation tube 199 is desirably closely sized to match the innerdiameter of the malleable handle shaft 130. In one embodiment, the outertube of the malleable handle shaft 130 has an OD of 0.197±0.003″(5.004±0.076 mm), and an ID of 0.153±0.002″ (3.886±0.051 mm). Theballoon inflation tube 199 has an OD of 0.140±0.002″ (3.556±0.051 mm),and an ID of 0.114±0.002″ (2.896±0.051 mm). This means the difference inradii between the ID of the larger tube 130 and the OD of the smallertube 199 is only 0.165 mm [(3.886-3.556)÷2], and the OD of the smallertube is more than 90% (91.5%) of the ID of the larger tube. This closematching of tube sizes ensures that the axial position of the balloon112, which is affixed to the end of the balloon inflation tube 199, doesnot shift much relative to the axial position of the prosthetic heartvalve 20, which is affixed relative to the end of the malleable handleshaft 130. The balloon extension wire 200 has a size relative to the IDof the balloon inflation tube 199 sufficient to permit good flow ofsaline when filling the balloon 112. In one embodiment, the wire 200 hasan OD of 0.037+0.002/−0.001″ (0.94+0.13/−0.025 mm).

The present delivery system advantageously prevents prematureadvancement of the balloon catheter so that the balloon 112 remainsretracted within the confines of the prosthetic heart valve 20 duringadvancement of the valve into position within the aortic annulus. Aswill be readily apparent, the surgeon advances the entire deliverysystem 110 with the heart valve 20 at its distal end through the openchest cavity or port and through the aortic arch and down the ascendingaorta into the implant position. Pushing on the proximal end of thedelivery system 110 carries the risk of accidentally displacing theballoon catheter relative to the handpiece 204 prior to the desireddeployment stage. A protruding balloon 112 may damage the coronary ostiaor make insertion difficult by enlarging the device profile.Consequently, the present application contemplates various means forphysically preventing movement of the balloon catheter, preferablycoupled with a visual reminder not to deploy the catheter prematurely.

For instance, FIG. 32 is a perspective view of the proximal end of theexemplary heart valve delivery system 110 showing a locking clip 240exploded therefrom. As seen in FIGS. 33A and 33B, the locking clip 240snaps to the exterior of the end cap 190 and handpiece 204 and holds theballoon catheter in a retracted position by presenting a physicalbarrier to relative movement of those two elements. The locking clip 240includes a semi-tubular body 242 terminating in a thumb ledge 244 on itsdistal end. The semi-tubular body 242 has internal features that matchthe external features on the handpiece 204. Specifically, although notshown, the interior of the semi-tubular body 242 has circumferentialridges that engage the proximal end of the handpiece 204 and bothfrictionally engage the handpiece and provide an impediment to distalaxial movement of the clip relative to the handpiece. The locking clip240 bifurcates into two elongated rails 246 that extend proximally fromthe body 242 and come together at a proximal bridge 248 having aninwardly-directed node 250 (FIG. 33B). The node 250 fits closely withinthe lumen of the luer adapter 192 and provides a physical barrier andvisual indicator to prevent premature attachment of a balloon inflationsource. Further, interior features on the two elongated rails 246 engagematching contours on the balloon catheter end cap 190.

The clip 240 assembles to the delivery system 110 as shown with theballoon catheter in the retracted position. First the node 250 insertsinto the luer adapter 192 lumen, and then the clip 240 snaps over theend cap 190 and handpiece 204. The connection between the clip 240 anddelivery system 110 is frictional and the clip can easily be removed,but provides a physical barrier and visual reminder to prevent prematuredistal deployment of the balloon catheter and connection of a ballooninflation source. Furthermore, the thumb ledge 244 on the clip 240provides a convenient ergonomic feature that facilitates control of thesystem advancement. After the surgeon advances the system and prostheticheart valve 20 into position within the aortic annulus, he/she removesthe clip 240 to enable deployment of the balloon catheter and connectionof an inflation source. The clip 240 is typically plastic and isdiscarded.

Other possible barriers to premature balloon catheter deployment/ballooninflation are contemplated. In one configuration shown in FIGS. 34 and35, a toggle lever 260 connects to both the end cap 190 and handpiece204 and may be displaced in either direction to alternately deploy andretract the balloon catheter. More specifically, the toggle lever 260includes a thumb piece 262 that projects outward from the deliverysystem 110, a hinge 264 pivotally mounted to the handpiece 204, and ablocking end 266 that fits in the axial space between the end cap 190and handpiece 204 in the retracted position of FIG. 34. A cam linkage268 pivotally attaches midway along the thumb piece 262 and pivotallyattaches at its opposite end to the end cap 190.

The retracted position of FIG. 34 corresponds to the retracted positionof the balloon catheter in the delivery system 110 as in FIG. 31. Inthis state, the blocking end 266 fits closely between the facingsurfaces of the spaced-apart end cap 190 and handpiece 204, and thuspresents a physical barrier to distal advancement of the end cap andballoon catheter within the delivery system 110. At the appropriatemoment, the surgeon pivots the toggle lever 260 in the direction of thearrow 270 in FIG. 35 which simultaneously removes the blocking end 266from between the end cap 190 and handpiece 204 and pulls the end captoward the handpiece by virtue of the cam linkage 268. Pivoting thetoggle lever 260 the full extent of its travel completely deploys theballoon catheter and displaces the balloon 112 to its proper positionwithin the anchoring skirt 26. That is, the distance traveled by the endcap 190 relative to the handpiece 204 is calibrated to be precisely thesame distance necessary to advance the balloon 112 to a location forproper expansion of the anchoring skirt 26 that ensures its optimumhemodynamic performance. Consequently, not only does the toggle lever260 prevent premature deployment of the balloon catheter, but it alsoensures advancement thereof prior to balloon inflation, and in so doingensures accurate advancement. Additionally, due to the connected natureof the toggle lever 260, there are no loose parts to interfere with theprocedure or potentially be misplaced during the surgery. Furtherdetails on ensuring the correct positioning of the balloon 112 withinthe skirt 26 are provided below.

When the surgeon pushes the toggle lever 260 into the advanced position,it desirably snaps into some feature on the handpiece 204 to signalcomplete deployment and to hold it in place. For instance, FIG. 36 showsa distal tip 272 of the lever 260 captured in a complementary notch orrecess in the exterior of the handpiece 204. Of course, numerous othersuch configurations are possible, and in general the toggle lever 260and its interaction with the end cap 190 and handpiece 204 are exemplaryonly. Alternatives such as sliders, rotating knobs or levers, colored oreven lighted indicators, etc., are contemplated. The purpose of suchalternatives is to prevent premature advancement of the ballooncatheter, ensure advancement before balloon inflation, and ensureaccurate advancement within the anchoring skirt 26 of the prostheticheart valve 20.

Other devices to prevent premature balloon catheter deployment/ballooninflation are contemplated, including physical impediments such as thetoggle lever 260 described above as well as visual or audible indicatorsto prevent deployment. For instance, an alternative configuration thatimpedes balloon inflation fluid flow prior to catheter advancement isseen in FIGS. 52-54 and described below.

FIGS. 37A-37C are perspective views illustrating deployment of theballoon catheter through the prosthetic heart valve and expansion of theballoon to expand the anchoring skirt, analogous to FIGS. 16E-16G.

FIG. 37C shows the balloon 112 inflated to expand and deploy theanchoring skirt 26 against the annulus. The anchoring skirt 26transitions between its conical contracted state and its generallytubular or slightly conical expanded state. Simple interference betweenthe anchoring skirt 26 and the annulus may be sufficient to anchor theheart valve 20, or interacting features such as projections, hooks,barbs, fabric, etc. may be utilized. For example, a distal end of theanchoring skirt (see lower edge 94 in FIG. 15B) may expand more than therest of the anchoring skirt so that peaks in the strut row farthest fromthe prosthetic valve project outward into the surrounding annulus.

Also, the balloon 112 may have a larger distal expanded end than itsproximal expanded end so as to apply more force to the free end of theanchoring skirt 26 than to the prosthetic valve member 24. In this way,the prosthetic valve member 24 and flexible leaflets therein are notsubject to high expansion forces from the balloon 112.

When assembled as seen in FIG. 30A, an elongated lumen (not numbered)extends from the proximal luer adapter 192 to the interior of theballoon 112. The luer adapter 192 provides an attachment nipple for aninflation system (not shown) for inflation of the balloon 112. Theballoon 112 is desirably inflated using controlled, pressurized, sterilephysiologic saline. The lumen passes through the end cap 190, balloondisplacer 198, and then through the inflation tube 199 which is affixedat one end to the displacer and at another end to a proximal end of theballoon. The balloon displacer 198 thus moves the proximal end of theballoon.

The present application also provides an improved balloon 112 and systemfor deploying and removing it. As seen in the deflated views, theballoon 112 preferably comprises a plurality of longitudinal pleatswhich help reduce its radial configuration for passage through thedelivery system 110. Furthermore, the balloon extension wire 200 extendsthrough the balloon inflation tube 199, through the dilatation balloon112, and terminates in a molded balloon wire tip 210 affixed to thedistal end of the balloon. The path of the wire 200 is seen in thesectional views of FIGS. 30A and 31A. Although the proximal end of theballoon 112 fastens to the inflation tube 199, and thus from there tothe handpiece 204, the distal tip 210 does not. Instead, the wire 200fastens to the spring compression pin 196 which translates within alumen in the proximal end cap 190, and engages the balloon extensionspring 194 therein. In this regard, the balloon extension wire 200 movesindependently within the delivery system 110 instead of being fixedlyattached. This, in turn, allows the distal end of the balloon 112 tomove with respect to the proximal end. This arrangement is seen best inFIGS. 38-40.

The exemplary delivery system balloon 112 has a relatively highdiameter-to-length ratio compared to other surgical balloons, such asthose used to expand cardiovascular stents. This makes it particularlydifficult for the balloon 112 to return to a small geometry upondeflation after deployment. Balloons of such size ratios tend to“butterfly” by forming wings that prevent removal through the valveholder without the application of high forces, which may cause damage tothe valve itself. The exemplary delivery system 110 and balloon 112include several advances from earlier heart valve delivery systems thatfacilitate a traumatic removal of the balloon 112. First, as mentionedabove, a series of longitudinal pleats are heat set into the wall of theballoon 112 to facilitate self-collapse during deflation. Further, thedistal end of the balloon 112 moves relative to the proximal end toenable lengthening of the balloon during deflation. This lengtheningoccurs automatically by virtue of the wire 200 which is spring-biased tostretch the balloon longitudinally. It should be noted that easydeflation and removal of the balloon 112 permits rapid replacement ofthe balloon catheter in case of a problem, such as insufficientinflation.

FIG. 38 is a sectional view with the balloon 112 advanced as in FIG.31A. In this configuration, the spring 194 has a length of x₁, and thespring compression pin 196 is all the way to the right within the endcap cavity. In this “resting” state with the balloon 112 deflated, thespring 194 may be relaxed or under a slight compressive preload.Subsequently, saline is introduced via the proximal luer connector 192and travels distally along the length of the balloon catheter componentsto inflate the balloon 112. Inflation of the balloon 112 causes radialexpansion but axial foreshortening, thus displacing the distal tip 210to the left as shown in FIG. 39. This, in turn, displaces the balloonextension wire 200 and attached spring compression pin 196 to the leftagainst the resiliency of the spring 194. Ultimately, the spring iscompressed to a second shorter length x₂. In a preferred embodiment, thespring 194 undergoes complete compression to its solid length so as toprovide a positive stop on proximal movement of the wire 200 andattached balloon distal tip 210. This helps ensure proper expansion ofthe anchoring skirt 26, as will be more fully explained. The proximalmovement of the distal tip 210 against the reaction force of the spring194 places the wire 200 in compression.

Finally, FIG. 40 illustrates deflation of the balloon 112 by pulling avacuum through the inflation movement and return movement to the rightof the distal tip 210 and balloon extension wire 200. This movement isencouraged, and indeed forced, by expansion of the spring 194. The forceof the spring 194 is calibrated so as to elongate the pleated balloon112 so it assumes its previous radially constricted diameter, or asclose as possible to it. Furthermore, the wire 200 may be rotated aboutits axis to further encourage constriction of the balloon 112 by causingthe pleats to further fold in a helical fashion. This can beaccomplished by extending a portion of the wire 200 from the proximalend of the Luer connector 192 so as to be grasped and rotated byforceps, or otherwise providing a lever or thumb plunger (not shown)fastened to the wire and projecting laterally from the system. Stillfurther, the spring compression pin 196 may be constrained to translatewithin a helical track. In the latter case, the pin 196 may include abayonet-type mount that locks within detents in both ends of the helicaltrack. The spring-biased lengthening and consequent radial contractionof the balloon 112 facilitates its proximal removal through thenow-deployed prosthetic heart valve 20.

As mentioned above, the balloon 112 desirably has a frusto-conicalprofile that expands the anchoring skirt 26 into a frusto-conicalexpanded state. More typically, and as shown in FIG. 39, the balloon 112is generally spherical when expanded. Nevertheless, a spherical balloonwill outwardly expand the anchoring skirt 26 into a frusto-conical shapedue to the connection at one end of the inner stent frame 80 to theheart valve sewing ring 62 (see FIGS. 15A/15B). To ensure sufficient andproper outward expansion of the anchoring skirt 26, the balloon 112 isaxially positioned such that a midline 280 indicated around the maximumcircumference (equatorial line) thereof registers with the distalmostend 282 of the skirt. In doing so, the widest part of the balloon 112corresponds to the end of the skirt 26, which tends to expand the skirtconically. A tolerance of 1-2 mm between the location of the midline 280and the distalmost end 282 of the skirt is acceptable which may occurfor different sizes of valves and associated skirt 26.

As seen in FIGS. 41-42 an exemplary stepped balloon construction isshown wherein the balloon 112 is desirably offset molded to form themidline 280 as a small step in the balloon wall. That is, the opposedballoon mold halves will have a slightly different diameter, such that aphysical step in the final product is formed—the midline 280.Alternatively, the midline 280 may be formed by a small equatorial ribor indent formed in the mold process, or even with an ink marking,though the latter may not be suitable for surgical application. Themidline 280 will be visible on the balloon 112 in both its deflated andinflated states, and is extremely useful as a reference line duringassembly and quality control of the delivery system 110. For instance,the components of the system 110 are assembled and the location of theballoon 112 in its advanced position is checked against the anchoringskirt 26. Since the balloon 112 foreshortens when it is inflated, thereference midline 280 should be beyond the distalmost end 282 of theskirt 26 when the balloon is deflated, a location that can easily beinspected during assembly.

Although FIGS. 41 and 42 illustrate a geometric molded shape of theexpansion balloon 112, in use, saline or other fluid injected into theballoon cavity will result in a more rounded inflated shape, such asseen in FIG. 39. The exemplary molded shape shown is preferred becauseof the relatively large diameter to which the distal end of the frame ofthe anchoring skirt 26 expands. More particularly, the exemplary shapeincludes proximal and distal tubular ends 290 to which elongatedelements of the balloon catheter are secured. A pair of conicalsidewalls 292 angle outward toward the midline of the balloon 112 fromthe tubular ends 290, while a pair of offset axial sidewalls 294, 296complete the balloon 112, spanning the midline or equator. One or theother of the axial sidewalls 294, 296 has a larger diameter, with theaxial sidewalls being joined at a step 298 that indicates the equatorialmidline 280 of the balloon 112. Again, this construction may be formedusing an offset mold, wherein one mold half is larger than the other.

Another advance regarding the balloon 112 is in the steps forcalibrating its fill capacity. Existing balloon catheters are calibratedby monitoring the volume injected to expand the balloon to a desireddiameter. In contrast, the balloon 112 for the delivery system 110 iscalibrated by pressure. One or more balloons are tested duringverification testing to see how much pressure is needed to expand ananchoring skirt 26 to a particular diameter, depending on the finaldesired size of the skirt. During assembly, each balloon is inflated tosee that it expands to within the expected range. In use, a pressuregauge attaches in the fill line to monitor the fill pressure. Thesurgeon inflates to the target pressure, and as further confirmation canverify the resulting skirt expansion visually or with the aid of a scopeor radiographic markers and the like.

It should be noted that the flared shape of the expanded anchoring stent26 (see FIG. 16H or FIG. 46A, below) may help improve flow through theprosthetic heart valve relative to a valve without the skirt. In somepatients, ventricular hypertrophy tends to cause an inward bulging ofthe left ventricle wall just below the aortic valve. The conical skirt26 will expand outward against this anomaly, and in doing so will expandthe inflow passage to the aortic valve.

The balloon extension wire 200 seen extending the length of the deliverysystem in FIGS. 38-40 flexes in order to adapt to bending of thesurrounding handle shaft 130 (e.g., see FIG. 29). In a preferredembodiment, the wire 200 is Nitinol, though other suitable metals suchas stainless steel could be used. Nitinol combines good column strengthwith excellent flexibility. However, the delivery system 110 will beprovided in an array of sizes for different sized orifice prostheticheart valves, and the largest balloons will exert a significantcompressive force on the wire 20 when inflated. To prevent the wire 200from buckling, and in lieu of stiffening the wire, a short hypotube 201may be provided, as seen in FIGS. 22 and 39. The hypotube 201 affixes tothe wire 200 at its distal end, such as by being molded together withthe wire and the balloon catheter tip 210 or other suitable means. Thehypotube 201 provides added column strength to the wire 200 along itslength that projects out of the inflation tube 199 and within theballoon 112. The hypotube 201 terminates just past the proximal end ofthe balloon 112 so as not to interfere much with the overall flexibilityof the delivery system 110. The hypotube 201 may be made of a suitablemetal such as Stainless Steel or a stiff polymer such as Nylon. Thehypotube 201 has an OD of 0.059±0.005″ (1.5±0.13 mm), an ID of0.041±0.003″ (1.04±0.08 mm), and a length of about 1.77″ (45.0 mm).

FIGS. 43-45 are external and sectional views of a distal end of theballoon extension wire 200 and distal insert molded tip 210 thereon—FIG.45B shows the final assembly in section, with the distal end of the wire200 embedded within the tip 210, while the other views illustrate anassembly process therefore. The insert molded tip 210 provides an anchorfor the distal end of the wire 200 which experiences high axial forcesduring balloon expansion. More particularly, and as explained above withreference to FIG. 39, balloon expansion causes outward expansion andaxial foreshortening such that the distal tubular end 290 (see FIG. 42)moves in a proximal direction. The wire 200 attaches to the distaltubular end 290 via the insert molded tip 210, and thus both moveproximally as well. As previously described, inflation of the balloon112 places the wire 200 in compression. Consequently, the connectionbetween the wire 200 and tip 210, and between the tip 210 and tubularend 290 of the balloon 112 must be relatively robust to avoid leakage orthe wire breaking free of the tip. Moreover, manufacturing concernsrequire as few steps as possible to form this important construct.

Accordingly, the distal end of the wire 200 is turned back on itselfinto a J-shaped bend 300. The bend 300 is then placed within an insertmold within which is injected material to form the molded tip 210, inthe combination shown in FIG. 45A. The shape of the tip 210 aftermolding is seen in FIGS. 44A-44D. The tip 210 after molding includes aproximal portion having a cylindrical shaft region 302 and asemi-spherical bulb 304, a distal portion including a tubular mandrelalignment conduit 306, and a narrow bridge 308 therebetween, identifiedin FIG. 44C. The mandrel alignment conduit 306 provides a convenienthandle of sorts to hold the tip 210 and wire 200 securely centeredwithin the distal tubular end 290 of the balloon 112 during a heatfusion step, typically with laser bonding. After bonding the balloon 112to the tip 210, the mandrel alignment conduit 306 is severed at thebridge 308, resulting in the rounded end shape for atraumatic deliveryas seen in FIG. 45B. The final tip 210 desirably has a relatively shortaxial length of between about 6-8 mm. The length of the wire 200 may be300-400 mm, and has a diameter of 1 mm or less.

An alternative assembly is seen in FIG. 45C, where the J-shaped bend 300on the end of the wire 200 has been replaced with a bead 300′. The bead300′ may be fused to the end of the wire 200 or adhered thereto. Indeed,the bead 300′ represents numerous other enlargements that could be usedon the end of the wire 200 to prevent it pulling free of the molded tip210. For instance, the end of the wire 200 could be compressed into abead or a flat head, much like a rivet, or the bead 300′ could be adifferent shape such as square to provide some torsional resistance.

The materials of the balloon 112 and tip 210 are desirably similar tofacilitate their bonding from the application of heat to theirinterface. For example, the balloon 112 and tip 210 may be formed fromNylon or a high durometer thermoplastic elastomer (TPE) such as PEBAX®.The distal tubular end 290 of the balloon 112 fits closely around theshaft region 302 and abuts a small shoulder 310 at the beginning of thesemi-spherical bulb 304. This construction of the heat fusion coupledwith the physical engagement between the end of the balloon and theshoulder 310 provides a redundant attachment system with high axial pullstrength. That is, the attachment system prevents disengagement of thetip 210 from the balloon 112, and also effectively resists separationleading to leaking. Furthermore, the J-shaped bend 300 presents ananchor of sorts within the material of the molded tip 210. Pull testshave demonstrated that the assembly can withstand 40 lb of pull forcewithout the wire 200 breaking free of the tip 210.

One important aspect of the present heart valve delivery system is theconfiguration of the expandable anchoring skirt 26 in terms of itsconstruction within the heart valve and also its shape upon expansion.FIGS. 46A and 46B illustrate the exemplary prosthetic heart valve 20both assembled and with the anchoring skirt 26 exploded from the valvecomponent 24. Again, the valve member 24 may be an “off-the-shelf”commercial prosthetic valve such as the Carpentier-Edwards PERIMOUNTMagna® Aortic Heart Valve available from Edwards Lifesciences. Theanchoring skirt 26 primarily includes the inner plastically-expandableframe or stent 80, with a fabric cover not shown for clarity.

As mentioned, the anchoring skirt 26 attaches to an inflow end of thevalve member 24, typically via sutures through the upper end 86 of thestent frame 80 connected to fabric on the valve member 24, or to thesewing ring 62. The particular sewing ring 62 shown includes anundulating inflow contour that dips down, or in the inflow direction, inthe regions of the valve cusps 34, and arcs up, in the outflowdirection, in the regions of the valve commissures 35. This undulatingshape generally follows the inflow end of the heart valve memberwireform 50 (see FIG. 10) which seats down within the sewing ring 62.The scalloped upper end 86 of the stent frame 80 also conforms to thisundulating shape, with peaks aligned with the valve commissures 35 andvalleys aligned with the valve cusps 34. Further details on exemplaryvalve/stent constructions are provided below with reference to FIGS.55-58.

With reference back to FIGS. 46-48, the stent frame 80 of the anchoringskirt 26 may be initially formed in several ways. For instance, atubular portion of suitable metal such as stainless steel may be lasercut to length and to form the latticework of chevron-shapedinterconnected struts. Other methods including wire bending and the likeare also possible. The resulting stent frame 80 is initially tubularwhen attached to the valve member 24, and is then crimped into theconical shape shown in FIGS. 47A and 47B in a first crimping step.Preferably, a distributed inward crimping force is applied at evenlocations around the stent frame 80, such as indicated by the arrows inthe figures. The frame 80 is fixed along and thus pivots inward aboutits scalloped upper end 86. The crimping forces are applied starting atabout the level of the valleys of the uneven upper end 86, asschematically indicated in FIG. 48A, leaving a short axial distancewhere the stent frame 80 remains cylindrical.

In a preferred second crimping step, shown in FIG. 48B, inward forcesare applied unevenly to curl the lower or distal end of the stent frame80 inward, resulting in a somewhat spherical distal end. To avoidcausing overlap between the struts of the plastically-expandable stentframe 80, the forces are desirably applied more at three locationsdistributed 120° apart so that a bottom plan view (see FIG. 7D) showsthe lower end having a trilobular shape rather than circular. This helpsreduce the leading end profile of the valve without compromising theability of the stent frame 80 to freely expand into the shape in FIG.46A. Regardless of the crimping method, the inflation balloon 112ultimately outwardly expands the inflow end of the stent frame 80 toform the conical shape of FIGS. 46A and 46B.

It should be mentioned that as an alternative to a balloon, a mechanicalexpander may be used to expand the anchoring skirt 26 shown above. Forinstance, a mechanical expander may include a plurality of spreadablefingers actuated by a syringe-like apparatus, as seen in co-pending U.S.Patent Publication No. 2010-0161036, filed Dec. 10, 2009, incorporatedabove. The fingers are axially fixed but capable of pivoting or flexingwith respect to a barrel. The distal end of a plunger has an outerdiameter that is greater than the diameter circumscribed by the innersurfaces of the spreadable fingers, such that distal movement of theplunger with respect to the barrel gradually cams the fingers outwardwithin the coupling stent. Therefore, the term “plastically-expandable”encompasses materials that can be substantially deformed by an appliedforce to assume a different shape. Some self-expanding stents may bedeformed to a degree by an applied force beyond their maximum expandeddimension, but the primary cause of the shape change is elastic reboundas opposed to a plastic deformation.

In accordance with one alternative embodiment, FIGS. 49-50 show anexpansion system including mechanical fingers 320 in conjunction with aninflatable balloon 322 for expanding the anchoring skirt 26. FIG. 50Aillustrates the mechanical fingers 320 surrounding the balloon 322 andextending from a handle attachment member 324 that is partly insertedinto the inflow end of a prosthetic heart valve 20 as described herein.The assembly of the attachment member 324, mechanical fingers 320 andballoon 322 is shown in cross-section in FIG. 49. The handle attachmentmember 324 includes a lumen 326 therethrough having internal threading328 on a proximal end. A malleable handle such as that described abovemay be threaded onto the proximal end of the attachment member 324 andsupply inflation fluid for the balloon 322.

The mechanical fingers 320 may be hinged about a distal end of theattachment member 324, such with living hinges 330 as seen in FIG. 49and in the detail of FIG. 50E. In a preferred embodiment, the livinghinges 330 are each formed by a V-shaped notch having an included angleφ that limits outward movement of the fingers 320. The fingers 320 maybe slightly tapered so as to be radially thicker on the distal ends. Asthe assembly inserts within the heart valve 20, such as from theposition in FIG. 50A to the position in FIG. 50B, the inflow aspect ofthe valve having the anchoring skirt 26 eventually contacts the exteriorsurfaces of the fingers 320. Further relative movement increases thefrictional fit between the interior of the skirt 26 and the exterior ofthe fingers 320 (biasing the fingers inward against the resiliency ofthe balloon 322) until a series of outwardly-directed detents 340 engagethe struts of the stent frame 80, as seen in FIG. 50E. The detents 340comprise small angled cutouts that define hooks on the distal ends ofthe fingers 320, the cutouts being oriented at angle θ with the radialthat optimally captures the struts of the anchoring skirt 26. This locksthe position of the mechanical fingers 320 relative to the anchoringskirt 26. Inflation of the balloon 322, as seen in FIG. 50E, pivots themechanical fingers 320 outward about the living hinges 330, forcing thedistal end of the anchoring stent 26 outward into contact with thesurrounding anatomy. The V-shaped notches forming the living hinges 330limit outward rotation of each of the fingers 320 to a predeterminedmagnitude so as to avoid over expanding the anchoring stent 26.

In use, the expansion assembly of the mechanical fingers 320, balloon322, and attachment member 324 are inserted through the inflow aspect ofthe prosthetic heart valve 20 until locked into position with thedetents 340 engage with the distal end of the skirt 26. Subsequently, ahollow-shaft of malleable handle may be attached to the proximal end ofthe attachment member 324. Alternatively, the prosthetic heart valve 20can be sutured and parachuted in situ with the expander assemblyinserted but without a handle attached. Upon satisfactory placement ofthe valve 20 in situ, a conventional inflation device along with thehandle may be connected to the attachment member 324 for inflating theballoon 322. Deflation of the balloon 322 after installation of theheart valve 20 causes the mechanical fingers 320 to pivot inward again.The fingers 320 may be bonded to the exterior of the balloon 322 tofacilitate inward retraction thereof when the vacuum is applied to theballoon.

Alternatives to the expansion assembly of FIGS. 49-50 include mechanicalfingers that are not pivotally attached to a handle attachment member.In this way, an inflation balloon causes direct radial expansion of thefingers instead of a pivoting movement. Furthermore, an elongatedmalleable handle may be provided as one piece with the attachment member324, rather than as a threaded coupling.

As mentioned previously, the present application contemplates variousalternatives for ensuring that the valve inflation balloon does notprematurely inflate. For example, FIGS. 51-54 schematically illustratesystems where a port for fluid used to inflate the balloon on thecatheter must be first opened prior to balloon expansion.

FIG. 51 is an elevational view of a portion of the proximal end of analternative delivery system 110 similar to the views of FIGS. 34-36, andshowing the relatively movable end cap 190 and handpiece 204. A tubularextension 350 of the end cap 190 shown schematically in FIG. 52Aincludes a closed distal end 352 and a pair of side ports 354 justproximal to the distal end. The tubular extension 350 fits closelywithin a bore 356 formed in a proximal end of the handpiece 204. Priorto balloon expansion, the components are positioned as seen in FIG. 52B,with the distal end of the tubular extension 350 positioned within thebore 350 such that the side ports 354 are blocked. Distal movement ofthe end cap 190 as seen in FIG. 52C causes the tubular extension 350 toproject from within the bore 356 into a larger chamber 358, thusexposing the side ports 354 so the fluid may be injected toward thedistal balloon. In this configuration, the end cap 190 must first movedistally relative to the handpiece 204 before fluid can be injected toinflate the balloon.

FIG. 53 also shows a portion of the proximal end of an alternativedelivery system 110 similar to the views of FIGS. 34-36, with therelatively movable end cap 190 and handpiece 204. A tubular extension360 of the end cap 190 shown exploded in FIG. 54A again includes adistal end closed by a plunger 362 and has a pair of side ports 364 justproximal to the distal end. The tubular extension 350 fits closelywithin a bore 366 formed in a proximal end of the handpiece 204. Priorto balloon expansion, the components are positioned as seen in FIG. 54B,with the plunger 362 sealed against the opening to the bore 366 suchthat the side ports 364 are blocked. Distal movement of the end cap 190as seen in FIG. 54C causes movement of the plunger 362 into a largerchamber 368, thus opening the side ports 364 so the fluid may beinjected toward the distal balloon. Again, this configuration ensuresthat the end cap 190 must first move distally relative to the handpiece204 before fluid can be injected to inflate the balloon.

Various heart valves may be utilized in combination with the deliverysystem components described herein, and any combination not otherwiseexplicitly described is contemplated. For instance, FIG. 55 is aperspective view of an exemplary prosthetic heart valve 400 having acommercially available valve member 402 coupled with an anchoring stent404 minus a surrounding fabric cover. FIG. 55A is a radial sectionalview through a cusp portion of the heart valve 400 with a fabric cover406 of the skirt stent 404 shown. Finally, FIG. 56 is an explodedelevational view of the prosthetic heart valve 400 of FIG. 55. Theparticular valve member 402 shown is the Carpentier-Edwards PERIMOUNTMagna® Aortic Heart Valve available from Edwards Lifesciences of Irvine,Calif. As seen in FIG. 55A, the Magna valve has a structure including awireform 410 wrapped in a cloth cover 412 and attached to acloth-covered axial band structure 414 with flexible bioprostheticleaflets 414 sandwiched therebetween. A highly flexible sewing ring 416attaches to the outside perimeter of the band structure 414 as shown.Finally, the cloth-covered anchoring skirt 404 is secured at a buttjoint to an inflow end of the Magna valve, such as with sutures throughthe respective cloth covers and desirably through the stent frame of theskirt 404 and through apertures in the band structure 414, as describedabove. The sewing ring 416 attaches to the band structure 414 along aline of stitching, rendering it easily flexed outward. Further, thesewing ring 416 has a relatively thin-walled silicone insert 418 with ahoneycomb structure. That is an advantage for conventional valves, butmay not be quite so desirable for valves as described herein.

In contrast, FIG. 57 shows an alternative prosthetic heart valve 420similar to that shown in FIG. 55 but having a different, firmer sewingring 422. In particular, FIGS. 58A and 58B are radial sectional viewsthrough the prosthetic heart valve 420 illustrating alternativeconstructions of the sewing ring 422. Like elements will be given likenumbers.

In both FIGS. 58A and 58B the sewing ring 422 secures to the outside ofthe band structure 414 along a cylindrical region of stitching 424,which helps reduce up and down flexing of the sewing ring 422. Secondly,the sewing ring 422 in FIG. 58A comprises a solid yet compressiblematerial that is relatively stiff so as to provide a seal against theannulus and has a concave inflow shape that conforms to the annulus.Desirably, the sewing ring 422 includes a closed-cell foam insert 430within a cloth cover. There are no cavities/cells, which makes thesewing ring 422 soft to the surrounding tissue yet relatively stiffoverall. Moreover, the concave inflow side matches that of the annulusfor better sealing therebetween. FIG. 58B shows an additionalreinforcing member 432 embedded within the insert 430 that stiffens thesewing ring 422 even further. The reinforcing member 432 may bemetallic, such as stainless steel or the like. Both sewing rings 422 arestiffer than the Magna sewing ring and thus create a better seal againstthe aortic valve annulus in opposition to the outwardly expandedanchoring skirt within the left ventricle. The combination provides arelatively secure anchoring structure for the valves disclosed herein,and helps prevent paravalvular leaking around the outside of the valveby matching the shape of and firmly holding the soft material againstthe annulus.

Once again, the cloth-covered anchoring skirt 404 is secured at a buttjoint to an inflow end of the Magna valve, such as with sutures throughthe stent frame of the skirt 404 and through apertures in the bandstructure 414. Furthermore, the lower end of the sewing ring 422desirably overlaps the anchoring skirt 404 by a short distance and thestitching 424 extends down therebetween. This further enhances thestiffness of the assembly, thus improving seating and sealing againstthe aortic annulus. Although not shown, the sewing ring 422 may beannular but is desirably slightly scalloped so as to better conform tothe aortic annulus. The stiff scalloped sewing ring 422 assists thesurgeon in rapidly seating the prosthetic valve in place by providing afirm platform to mate against the contours of the undulating aorticannulus.

It should be noted that a sewing ring per se may not be necessary withthe present heart valve as the primary function of such a component isto provide a platform through which to pass a number of anchoringsutures around the valve periphery, which is not used here exceptperhaps for several (e.g., 3) guide sutures. Consequently, the valvemembers described herein could be coupled to the anchoring skirtdirectly without a sewing ring. To help prevent paravalvular leaking aperipheral seal such as a fabric skirt may be added in place of thesewing ring. Also, several tabs extending outward from the valestructure could be used for anchoring the guide sutures which take theplace of the sewing ring for that purpose.

The system disclosed herein is also desirably used with a particularvalve annulus sizing technique. The sizing apparatus (not shown)includes a catheter shaft having a compliant balloon on a distal endthat can be inflated with saline. An intravascular ultrasound (IVUS)imaging probe extends through the catheter and within the compliantballoon. After preparing the patient for surgery, but prior tointroduction of the delivery system 110, the balloon catheter isintroduced into the valve annulus. The balloon is filled to a desiredpressure, and the IVUS probe is advanced through the catheter and intothe balloon. Because the balloon conforms to the anatomical cavitysurrounding it, the IVUS probe measures the size of that cavity.

The advantage of being able to expand the native annulus with theexpandable skirt to receive a larger valve size than would otherwise bepossible with conventional surgery was mentioned above. Another way toaccomplish such enlargement is to utilize a tapered dilator, such as aHagar dilator. The conical dilator has a maximum diameter that is largerthan the anticipated valve diameter. By passing the dilator into theannulus prior to installation of the valve, a larger valve may beselected. Furthermore, the larger valve temporarily fits within theannulus, but the resiliency of the tissue constricts around the valvefor a more secure anchor.

While the invention has been described in its preferred embodiments, itis to be understood that the words which have been used are words ofdescription and not of limitation. Therefore, changes may be made withinthe appended claims without departing from the true scope of theinvention.

What is claimed is:
 1. A prosthetic heart valve for implant at a heartvalve annulus, comprising: a non-expandable, non-collapsible annularsupport structure defining a flow orifice and having an inflow end;valve leaflets attached to the support structure and mounted toalternately open and close across the flow orifice; aplastically-expandable frame having an outflow or first end extendingaround the flow orifice and connected to the valve at the inflow end ofthe support structure, the frame having an inflow or second endprojecting in the inflow direction away from the support structure andbeing capable of assuming a contracted state for delivery to an implantposition and a wider expanded state for outward contact with an annulus;and a fabric covering around the plastically-expandable frame includingan enlarged sealing flange surrounding the second end.
 2. The heartvalve of claim 1, wherein the support structure includes a plurality ofcommissure posts projecting in an outflow direction, and the valveleaflets are flexible and attach to the support structure and commissureposts.
 3. The heart valve of claim 1, wherein in the contracted statethe frame is generally conical, tapering inward from the first endtoward the second end.
 4. The heart valve of claim 3, wherein the firstend of the frame has a scalloped shape with peaks and valleys, and inthe contracted state the frame is cylindrical between the peaks andvalleys and conical from the valleys to the second end.
 5. The heartvalve of claim 3, wherein the second end of the frame curls inward. 6.The heart valve of claim 1, wherein in the contracted state the secondend of the frame has a trilobular shape as seen looking in the outflowdirection.
 7. The heart valve of claim 1, further including a sealingring circumscribing the inflow end of the support structure.
 8. Theheart valve of claim 7, wherein the sealing ring comprises a solid yetcompressible material that is relatively stiff so as to provide a sealagainst the annulus and has a concave inflow shape that conforms to theannulus.
 9. The heart valve of claim 8, wherein the sealing ring has aconcave inflow shape that conforms to the heart valve annulus.
 10. Theheart valve of claim 7, wherein the sealing ring attaches to the supportstructure along a line of stitching, rendering it easily flexed outward.11. A prosthetic heart valve for implant at a heart valve annulus,comprising: a non-expandable, non-collapsible annular support structuredefining a flow orifice and having an inflow end; valve leafletsattached to the support structure and mounted to alternately open andclose across the flow orifice; a relatively stiff sealing ring securedto and projecting outward from the inflow end of the support structure;and a plastically-expandable frame having a first end extending aroundthe flow orifice and connected to the valve at the inflow end of thesupport structure, the frame having a second end projecting in theinflow direction away from the support structure and being capable ofassuming a contracted state for delivery to an implant position and awider expanded state for outward contact with an annulus, wherein thesealing ring and frame in its expanded state are spaced apart tosandwich the heart valve annulus therebetween.
 12. The heart valve ofclaim 11, wherein the sealing ring secures to the outside of the supportstructure along a cylindrical region of stitching to help reduce up anddown flexing of the sealing ring.
 13. The heart valve of claim 11,wherein the sealing ring comprises a closed-cell foam insert within acloth cover.
 14. The heart valve of claim 11, wherein the sealing ringhas a concave inflow shape that conforms to the heart valve annulus. 15.The heart valve of claim 11, wherein the sealing ring comprises a foaminsert with a reinforcing member embedded therein.
 16. The heart valveof claim 15, wherein the reinforcing member is metallic.
 17. The heartvalve of claim 11, wherein the first end of the frame is secured at abutt joint to the inflow end of the support structure, and a lower endof the sealing ring overlaps the first end of the frame with stitchingtherebetween to enhance the stiffness of the assembly.
 18. The heartvalve of claim 11, wherein the prosthetic heart valve is adapted forimplant at an aortic valve annulus having an undulating shape, and thesealing ring has a scalloped shape to match the undulating shape of theaortic valve annulus.
 19. The heart valve of claim 18, further includinga fabric covering around the plastically-expandable frame including anenlarged sealing flange surrounding the second end, the frame size toexpand within the left ventricle and contact the wall thereof under theaortic annulus.
 20. The heart valve of claim 11, wherein the first endof the frame has a scalloped shape with peaks and valleys, and whereinin the contracted state the frame is cylindrical between the peaks andvalleys and conical from the valleys to the second end.